Variolab – A/B Testing

curl -I https://yoursite.com/promo/

curl -u 'admin:xxxx xxxx xxxx xxxx xxxx xxxx' 'https://yoursite.com/wp-json/abtest/v1/stats?status=running'

Changelog

0.20.0

• New conversion goal: “HubSpot form submitted”. Embedded HubSpot forms render inside a cross-origin iframe, so a CSS-selector “click” goal can never reach the submit button (the browser blocks it). This new goal type listens for HubSpot’s own form-submission event (the hsFormCallback message HubSpot posts to the page — the same hook Google Analytics / GTM use), verifies it really comes from a HubSpot origin, and records the conversion. Leave the goal value empty to count any HubSpot form submission on the test page, or paste a HubSpot form GUID to count only that specific form. When you preview a running test as a logged-in admin, the browser console logs each HubSpot event so you can confirm the wiring with one test submission.

0.19.0

• Clearer cache diagnostics on the A/B Tests list. The “Cache check” box now shows what was detected as neutral chips — Kinsta, Cloudflare, your cache plugin, and a cache detected indicator (blue/grey, because a site-level cache is normal and not a problem in itself; only your test URLs must bypass it). When a cache is present, a single bold, highlighted line spells out what matters — make sure every test URL above shows “out of cache” — followed by short, host-specific guidance (e.g. the Kinsta Cache Bypass steps, and the one-click cache-resilient mode). The separate caching admin notice that used to sit at the top of the screen is gone: everything now lives in one place, right next to the per-URL pills it refers to. Per-test pills still turn red CACHED when a test page is wrongly served from cache.

0.18.0

• Your data now survives a plugin delete. Deleting the plugin used to run the uninstaller, which dropped the events table and removed every experiment, page-import record, and setting — so anyone who “deleted + reinstalled” to upgrade lost all their A/B history. The uninstaller now keeps your data by default: an accidental delete (or a delete-to-reinstall) no longer wipes anything. Always use the normal Update action to upgrade (Plugins → Update, or wp plugin update); only delete when you really want the plugin gone. A new Settings → Data & uninstall section explains this and offers an opt-in “Delete all data on uninstall” checkbox (off by default) for when you want a clean removal that erases everything.

0.17.1

• Cache check polish. The “how to fix it” guidance now appears in the Cache check box only when an active cache is actually detected (instead of always living in Settings). And a test page handled by cache-resilient mode now reads CACHE RESILIENT MODE (amber) instead of the ambiguous “CACHED (RESILIENT)”.

0.17.0

• Cache check on the A/B Tests list. Each running test now shows a status pill — out of cache ✓ or CACHED ⚠️ — so you can confirm at a glance that your test pages bypass the cache (a cached test page freezes the variant and drops conversions). A baseline pill checks a normal page too, which should be cached, confirming your cache works in general. The check runs from your browser, anonymously, and never logs an impression (it sends a header that tells the plugin to skip counting). Choose Smart (auto, refreshed in the background) or Manual (only on the “Re-check” button) in Settings → Caching & CDN — handy if you run many tests.

0.16.0

• Caching & CDN: new guidance + an opt-in “Cache-resilient mode”. A cached A/B test page breaks the test (one variant frozen for everyone, conversions silently dropped because WordPress never runs to log the impression). New in Settings → Caching & CDN: clear, host-specific instructions for excluding test URLs from your cache (Cloudways/Varnish, Cloudflare, Kinsta, nginx…), and a one-click Cache-resilient mode that forces a fresh render via a one-time ?_abtcb=… redirect when you can’t edit your cache rules. The admin cache notice now also detects Cloudflare and points to both options. (Default off; recommended fix remains a proper cache exclusion.)

0.15.11

• Fix conversions with WP Rocket “Delay JavaScript Execution” (the real “click twice” cause). When that optimisation is on (also in Perfmatters and similar), it defers every script until the visitor’s first interaction — so the very first click only woke the tracker up and wasn’t recorded, and you had to click again. The conversion tracker is now automatically excluded from delay-JS, so it runs on page load and the first click counts. If you use another delay-JS tool, exclude variolab-ab-testing/assets/js/tracker.js and AbtestTracker from it manually.

0.15.10

• Conversions no longer depend on the variant cookie (“had to click twice” fix). A conversion was only recorded if the visitor’s variant cookie was present, which could be missing on the first click (a CDN stripping the Set-Cookie header, or first-paint timing) — so the conversion was lost and you had to click again. The variant is now determined from the visitor’s server-side impression instead, so a real click counts the first time even if the cookie didn’t arrive. As a bonus this is also more tamper-resistant: a forged cookie can no longer attribute a conversion to a different variant.

0.15.9

• Conversion goals now work on imported HTML landing pages. Click and URL conversion goals previously never fired on pages imported via Import HTML (Blank Canvas), because the conversion tracker was only loaded on regular theme pages. The tracker is now injected into imported landings too, so “click a button matching a CSS selector” and “visit/click a URL” goals are recorded for real visitors. If your test runs on an imported page, this is the fix that makes its conversions count.
• New admin preview mode for goals. When you view a running test page while logged in (as an admin/editor — your visits are never counted), the page now shows a small “A/B preview” badge, outlines every element your CSS-selector goal matches, and pops a toast when you click one — so you can confirm a goal is wired correctly without polluting your stats.

0.15.8

• Visitor-dedup salt decoupled from WordPress auth keys. The de-duplication hash used wp_salt('auth'), so rotating your site’s authentication keys silently reset visitor de-duplication (re-counting returning visitors). It now uses a dedicated salt seeded once from the current auth salt — existing counts are preserved (no reset on update), and future key rotations no longer disturb your stats. Last clean-up item from the 2026-06-12 internal security audit.

0.15.7

• Make the HTML-import trust boundary explicit (defence-in-depth). Imported pages are rendered with no theme wrapper, so any markup they contain runs as-is. The plugin now records, at import time, whether the importer was allowed to store raw HTML/JS (the unfiltered_html capability) and, when rendering, re-filters anything that wasn’t through WordPress’s standard sanitizer. Single-site admins and existing imported pages are unaffected; the feature also remains available to multisite site administrators (their content is simply sanitized as WordPress already does on save). Closes the last actionable item from the 2026-06-12 internal security audit.

0.15.6

• Security hardening (defence-in-depth, from the 2026-06-12 audit). Four low-severity items addressed: HTML import “replace existing” now refuses any target that is not a page (can no longer be coerced into overwriting an arbitrary post); the watch-directory scanner verifies the resolved index file stays inside its folder (rejects symlink escapes); the webhook Secret help text now recommends a constant-time signature comparison (hash_equals()); and a misleading .gitignore entry was cleaned up. No functional change for normal use.

0.15.5

• Fix “translation triggered too early” PHP notice (WP 6.7+). The custom 5-minute cron interval registered a translated display label from the cron_schedules filter, which fires before the init action — tripping WordPress 6.7+’s _load_textdomain_just_in_time notice on every cron run (visible with WP_DEBUG and flagged by Plugin Check). The label, only ever shown in cron-management tools, is no longer translated, so nothing loads the text domain early. No functional change.

0.15.4

• Security: webhooks can no longer be pointed at internal addresses (SSRF hardening). Outgoing event webhooks now refuse URLs whose host is a loopback, link-local, private, or reserved IP — both when you save them (literal IPs like 127.0.0.1, 169.254.169.254, 10.0.0.0/8, 192.168.x) and at request time, where WordPress resolves the hostname and rejects targets that point inside your network (reject_unsafe_urls, which also blocks redirect-based bypasses). Legitimate public endpoints (Zapier, Make, Slack, your own API) are unaffected. Hardening from the 2026-06-12 internal security audit.

0.15.3

• Security: conversions now require a prior impression. The public conversion endpoint used to log a conversion based on a cookie value, which a client fully controls — so a request with a hand-crafted cookie for a guessed experiment ID could record conversions that never happened and skew a test’s result. Conversions are now only recorded when the visitor already has a server-side impression for that exact experiment and variant (impressions are written by the server when the page is actually served, and cannot be forged). Every real conversion therefore moves in lock-step with an impression, keeping the conversion rate honest. No change to legitimate tracking. Hardening from the 2026-06-12 internal security audit; combines with the existing per-IP rate limit and per-visitor dedup.

0.15.2

• Admin notices reposition. Third-party admin notices (security plugins, cache plugins, the plugin’s own CacheNotice, etc.) used to land between the Variolab brand header and the page content, pushing the table down. They now appear above the brand header — same slot WordPress uses on every other admin screen. Implemented via the standard <hr class="wp-header-end"> marker injected at the top of Admin::render_brand_header(), so all four plugin pages (List / Edit / Settings / Import) get the fix.

0.15.1

• Fix fatal error on imported HTML landings. templates/blank-canvas.php called UrlScripts::render_for_position(), which was never defined on the class — every visit to an HTML-imported page running an A/B test crashed with Call to undefined method. Added the missing method as the return-string counterpart of the existing print_for_position(); themed pages are unaffected.

0.15.0

• List page redesign. New branded dashboard at A/B Tests: header with Variolab brandline (icon + wordmark + version pill); 5-card KPI strip (Active tests / Impressions / Conversions / Overall rate / Winners shipped) driven by a new Stats::overview_kpis() aggregator; toolbar with 5 status chips (All / Draft / Running / Paused / Ended) + date range with 7d/30d/All-time presets; URL blocks rendered as cards with per-experiment 3-column CSS grid; ended experiments collapse into a native <details> per URL block. Cream canvas (#EFECE4) replaces the wp-admin gray across every plugin admin screen (scoped via body.toplevel_page_abtest-experiments).
• Inline SVG sparklines, Chart.js dropped. Replaces the ~205 KB vendored Chart.js + the assets/js/url-charts.js wrapper with a ~200-LOC vanilla list-interactions.js that renders an SVG polyline per (experiment, variant) using a 12-hex rotating palette so the chart line color matches the variant tag color in the row above. Variant A renders solid, B/C/D dashed. Dashed light-gray vertical markers show each experiment’s start + end dates with hover tooltip.
• Shared brand shell across all admin pages. New Admin::render_brand_header( $title ) helper applied to List / Edit / Settings / Import; the legacy form-table styles on Edit / Settings / Import are preserved by the dual wrap vlab-page abtest-wrap class so the form submission paths are unchanged.
• Inter Tight + JetBrains Mono variable fonts bundled as WOFF2 with a Latin Unicode subset (~200 KB total via pyftsubset). SIL OFL 1.1 license files shipped alongside.
• New ?status_filter=all|draft|running|paused|ended query arg replaces the old ?show=. The legacy parameter is translated silently for one release so bookmarks keep working.
• New CSS architecture: admin-tokens.css (design tokens + @font-face, everywhere) → admin-shell.css (cream bg + brandline + buttons, everywhere) → admin-list.css (list-specific, list page only). The legacy admin.css is kept verbatim for the other pages.
• Internal naming preserved: Abtest\ PHP namespace, abtest_* hook / cookie / option / table prefixes, REST namespace abtest/v1, custom table wp_abtest_events. No DB / cookie / option breaking change.

0.14.0

• wp.org Plugin Review round 2 — all findings addressed.
• Slug variolab → variolab-ab-testing (matches the slug wp.org reserved on resubmission). Text domain mass-updated across every __() / _e() call, main file variolab.php → variolab-ab-testing.php, composer.json / package.json package names, phpcs.xml.dist text-domain element + file ref, tests/Integration/bootstrap.php require path, .github/workflows/{ci,release}.yml build folder + zip filename + header-version grep.
• HtmlImport hardening: zip extraction no longer writes .html / .htm / .js files to the uploads directory (wp.org policy: no code-bearing files in uploads even though the area itself is allowed). The main index.html is read directly from the zip into memory and stored in post_content instead — never touches disk. CSS, images, fonts continue to extract normally. Local JS the template referenced via <script src="./bundle.js"> will 404 at render time; admins can re-inject inline JS via the per-URL tracking-scripts feature.
• Per-URL tracking scripts refactor: UrlScripts::print_for_position() now wraps each entry via wp_print_inline_script_tag() — the WP-blessed inline-script helper — instead of raw echo. The new UrlScripts::parse_script_input() silently strips <script ...> / </script> wrappers the admin pastes, extracting src / async / defer / type / id attributes for fidelity. 11 unit tests cover plain JS / single wrapper / multi-script degraded mode / orphan tags / boolean attributes.
• CPT slug ab_experiment → abtest_experiment (wp.org requires ≥4-char prefixes; ab_ was too short). Menu slug ab-testing → abtest-experiments. New idempotent migration Plugin::pre_install_rename_post_type() runs at upgrade (DB schema v1.3.0 → v1.4.0) renaming every existing post_type row in one statement before the new CPT registers on init. Uninstall handler accepts both new and legacy slugs so old installs still get cleaned up.
• Internal Abtest\ namespace, abtest_* hook / cookie / option / table prefixes (already 6-char), and REST namespace abtest/v1 stay untouched — no breaking change for existing data.

0.13.0

• Renamed plugin to Variolab – A/B Testing (slug variolab). The wp.org Plugin Review Team flagged “Uplift” on two cumulative grounds: (1) it is the standard industry term for the A/B-testing lift metric (non-distinctive — every VWO/Statsig/Insider/etc. doc uses “uplift” to mean conversion-rate lift), and (2) UPLIFT® is a live USPTO trademark (Reg. 4973441, UPLIFT INC., San Francisco) in the same “Advertising, Business & Retail Services” class as the plugin. Variolab is an invented term (vario + lab) with no wp.org / USPTO / SaaS hit at name-pick time.
• Coordinated multi-file change: plugin header display name + text domain (uplift-ab-testing → variolab everywhere — every __()/_e() call across includes/), main plugin file uplift-ab-testing.php → variolab.php, composer.json/package.json package names, phpcs.xml.dist text-domain element + file ref + ruleset name, tests/Integration/bootstrap.php require path, .github/workflows/{ci,release}.yml build folder + zip filename + header-version grep.
• Internal naming kept untouched (no DB / cookie / option / hook breaking change for existing installs): Abtest\ PHP namespace, abtest_* hook/cookie prefixes, REST namespace abtest/v1, custom table wp_abtest_events, option keys (abtest_settings, abtest_db_version).

0.12.0

• Renamed plugin to Uplift – A/B Testing (slug uplift-ab-testing). The WordPress trademark guideline forbids the word “WordPress” in both the plugin display name and the slug — this rename closes the last remaining wp.org submission blocker.
• Coordinated multi-file change: plugin header, text domain (uplift-ab-testing everywhere — every __()/_e() call across includes/), main plugin file ab-testing-wordpress.php → uplift-ab-testing.php, composer.json/package.json package names, phpcs.xml.dist text-domain element, tests/Integration/bootstrap.php require path, release.yml + ci.yml build paths and zip filename.
• Internal naming kept untouched (no breaking change for existing installs): the Abtest\ PHP namespace, abtest_* hook prefixes, abtest_* cookies, REST namespace abtest/v1, custom table wp_abtest_events, and option keys (abtest_settings, abtest_db_version) all stay as-is. They’re internal — never visible to wp.org reviewers and never on a user URL.

0.11.3

• WordPress.org compliance — final Plugin Check cleanup:
  • wp-tests-config.php, phpunit.xml*, and phpcs.xml* are now excluded from the built plugin folder by both release.yml and ci.yml. They were leaking into the artifact and tripping missing_direct_file_access_protection (the test bootstrap doesn’t and shouldn’t have an ABSPATH guard).
  • Replaced languages/.gitkeep with languages/index.php (the canonical “Silence is golden” pattern). .gitkeep was rejected as a hidden file by Plugin Check.
  • Renamed two unprefixed locals in templates/blank-canvas.php ($insert_at → $abtest_insert_at, $body_close → $abtest_body_close). Template files run in global scope, so unprefixed top-level vars trip PrefixAllGlobals.NonPrefixedVariableFound.
• Plugin Check on the built artifact is now green: 0 errors, 0 warnings.

0.11.2

• WordPress.org compliance hardening (post-Plugin-Check first run):
  • Plugin Check CI now runs against the built plugin folder (mirroring release.yml‘s rsync) instead of the raw repo, so dev-only files (tests/, .claude/, .github/, CLAUDE.md, composer.json, etc.) no longer pollute the report. Cuts ~80% of the false-positive noise.
  • ignore-codes list added with one-line rationale per entry: custom-table direct queries, file-system ops on plugin-controlled paths, mt_rand/mt_srand for variant picking, meta_query slow-query warnings, the init core-hook false positive.
• Removed load_plugin_textdomain() call: WordPress.org auto-loads translations for hosted plugins since WP 4.6 — manual loading is now discouraged. Text-domain header stays declared so JIT loading still works.
• Added empty languages/ folder (with a .gitkeep documenting why) to satisfy the Domain Path: /languages plugin header — Plugin Check (and wp.org reviewers) flag the header when the folder doesn’t exist.

0.11.1

• WordPress.org compliance: Chart.js (used to render the per-URL conversion-rate timeline on the admin list view) is no longer loaded from the jsdelivr CDN — it’s now bundled under assets/js/vendor/chart.umd.min.js. This satisfies the wp.org plugin guideline #5 “Trying to remotely load code”. MIT license attribution + update instructions are documented in assets/js/vendor/README.md.
• New CI step: WordPress’s official plugin-check-action runs on every push to main and PR. Same automated checks as the wp.org reviewers (plugin headers, i18n, late escaping, deprecated APIs, internationalization). Any future regression that would be flagged at submission time is caught at push time instead.

0.11.0

• New: per-URL no-index toggle. A new “SEO” row on the experiment edit form lets you mark any test URL as no-index. When checked, every visit to that URL emits both a <meta name="robots" content="noindex,nofollow"> tag and a matching X-Robots-Tag HTTP header — regardless of which experiment is currently running. Recommended for landing pages dedicated to paid traffic, or any URL where you don’t want both A/B variants to compete in search results.
• The setting is URL-scoped (stored in a new abtest_url_settings option keyed by URL path) so every experiment that lands on the same URL inherits it. Future URL-scoped flags can plug into the same store.
• New Abtest\UrlSettings helper class with 7 unit tests covering normalization, default pruning, and per-URL independence.

0.10.1

• i18n cleanup: every committed file is now in English. The plugin’s user-facing strings (HelpTabs, StatsExplain) ship as English source so the standard WordPress translation pipeline (.pot / .po) can produce localized versions later. Audit reports, todo, slash commands, internal rules, lessons-learned all translated. CLAUDE.md adds an explicit “English only in the repo” rule to prevent regressions.

0.10.0

• New: WordPress contextual help on the A/B Tests screens. Click “Help” at the top-right of any A/B Tests page to get 4 didactic tabs: Quick start, Stats explained (p-value / α / “no winner” reasons), Multi-variant (Bonferroni correction), Privacy & GDPR. Designed for non-statisticians installing the plugin for the first time.
• New: contextual tooltip on the “No winner” badge in the experiments list. Hover (or screen-reader-focus) the badge to see WHY this experiment doesn’t have a winner — the explanation auto-detects between: “too early” (running < 14 days), “sample too small” (< 200 imp/variant), “borderline” (p just above α), “genuine null result” (rates within ±15%), or generic “keep the test running”. Powered by a new pure-function helper Abtest\Admin\StatsExplain with 8 unit tests covering each branch.

0.9.3

• PHPCS WordPress Coding Standards : repaid the 1083-finding cosmetic dette. The codebase is now fully WPCS-clean and the GitHub Actions lint job is BLOCKING (was continue-on-error). Any new code that violates the ruleset fails the build.
• phpcs.xml.dist relaxed for modern PHP 8.1+ idioms : short array syntax [], short ternary ?:, alignment, and trivial-method docblocks no longer enforced. All Security / SQL / i18n / capability / nonce sniffs remain strict.
• All phpcs:ignore annotations on the codebase carry a one-line justification (why the rule is suppressed at this site).
• Bonus i18n fixes : added missing translators: comments on all _n() / __() calls with placeholders so the .pot file can guide translators.
• Bonus naming fix : renamed Autoload::load($class) to Autoload::load($class_name) since class is a PHP reserved keyword as a parameter name.

0.9.2

• Security hardening sweep — all open findings from the v0.9.1 audit closed.
• HTML upload now performs a real MIME check (wp_check_filetype_and_ext()) on top of the extension allowlist — for .zip this catches a PHP file disguised as a zip via magic-byte mismatch.
• Webhook URLs are now refused if they don’t start with http:// or https:// (anti-SSRF basic — blocks gopher://, ftp://, webcal://, etc. that esc_url_raw() would otherwise accept).
• Public REST endpoint /abtest/v1/convert now rate-limits each visitor IP to 60 conversions per minute (filterable via abtest_convert_rate_limit_per_min). Returns HTTP 429 when exceeded. Prevents distributed flood from biasing experiment statistics.
• PSR-4 autoloader rejects class names containing .. defensively (anti-traversal hardening).
• .gitignore extended with .env, .env.*, wp-tests-config.php, *.local.php, *.key, *.pem, *.p12, secrets.json (preventive — none of these files exist today).
• PHPCS false-positive annotations added on file_get_contents() calls reading local files (4 spots) and on the intentional 5-minute Watcher cron interval.

0.9.1

• Security hardening (post-audit): outbound webhook POSTs now pass 'sslverify' => true explicitly so a third-party http_request_args filter can’t silently downgrade SSL verification. Aligns with the explicit setting already in the GA4 integration.
• HTML import error message corrected — used to say “Only .html and .htm files are accepted” even though .zip has been accepted since v0.7.0. Message now generated from the live ALLOWED_EXTS constant and reports the rejected extension.

0.9.0

• Multilingual support (WPML / Polylang): a single experiment with test_url = /promo/ now matches /fr/promo/, /en/promo/, /de/promo/, etc. The bundled MultiLanguage helper auto-detects WPML/Polylang and strips the language prefix from request paths before matching. Compound slugs (pt-br, en-us) supported. Mid-path occurrences of a language slug (e.g. /blog/fr/x/) are NOT stripped — only true URL prefixes.
• New filter abtest_request_path for custom multilingual setups: receives the normalized request path, returns whatever you want the matcher to see. Documented in README.
• Filter is opt-out for non-default behavior: remove_filter('abtest_request_path', [\Abtest\MultiLanguage::class, 'strip_language_prefix']).

0.8.2

• RGPD data minimization: visitor_hash is now stored as 16 hex chars (64 bits) instead of 64 chars (256 bits). Birthday-collision probability stays under 3e-8 even at 1M visitors per experiment, dedup integrity preserved, and the smaller surface harder to brute-force against IP+UA rainbow tables. DB schema bumped to v1.3.0 — migration auto-truncates existing visitor_hash values via SUBSTRING before the column ALTER (idempotent, runs before dbDelta).
• Privacy policy guide text updated to describe the 64-bit truncated hash.

0.8.1

• Tested up to WordPress 6.9 (was 6.5). Local dev env (wp-env) and the wp-phpunit test suite both bumped to 6.9.4.
• Fixed PHP notice on WP 6.7+ (“_load_textdomain_just_in_time was called incorrectly”) — load_plugin_textdomain now runs on init priority 0 instead of plugins_loaded.
• Performance: GET /wp-json/abtest/v1/stats now runs a single batched SQL query for N experiments instead of N individual queries (N+1 → 1). New public Stats::raw_counts_for_experiments() powers both the REST endpoint and the admin list — same SQL path everywhere.

0.8.0

• Privacy & consent gating (GDPR): new “Require consent” toggle in Settings — when on, the plugin sets no cookie and logs no event until the abtest_visitor_has_consent filter returns true. Without consent, visitors silently see Variant A (same path as out-of-target). Off by default, no breaking change.
• Native WordPress privacy guide content registered via wp_add_privacy_policy_content() — find it under Settings → Privacy → Policy Guide → Variolab – A/B Testing, ready to paste into your privacy policy.
• README now has a Privacy & GDPR section with copy-paste filter snippets for Complianz, CookieYes, and Cookiebot.
• New Consent helper class + 5 unit tests covering the 4 gate states (off, on+true, on+false, on+null/missing filter).

0.7.0

• HTML import accepts .zip archives — extracts CSS/JS/images to wp-content/uploads/abtest-templates/{slug}/, rewrites relative asset URLs in the HTML so the page renders with full styling (security: extension allowlist + path-traversal guard).
• Watch directory: drop or edit index.html files in wp-content/uploads/abtest-templates/{slug}/ from your IDE, SFTP, or cloud sync — WP-Cron syncs changed files into pages every 5 minutes (or click “Scan now” in the Import HTML page). Hash-based change detection skips unchanged files.
• URL targeting now matches query strings (subset semantics): test_url = /promo/?campaign=fb matches visitor URL /promo/?campaign=fb&utm_source=email. Param order is canonicalized.
• URL targeting accepts Unicode paths: test_url = /promotion-été/ matches both the raw and percent-encoded request paths.
• Validation regex updated to accept Unicode lowercase letters/digits (was ASCII-only). HTML form pattern= constraint removed accordingly.

0.6.1

• Targeting refinement: out-of-target visitors now silently see the baseline (Variant A) instead of getting a 404 on custom URLs. They are NOT tracked — no cookie set, no impression logged, no conversion script enqueued. Out-of-target visitors on URLs that override an existing public page still fall through to that original page (unchanged).
• The point: ad-paid traffic from outside your target audience (geo or device) doesn’t waste clicks on 404s and doesn’t pollute your test stats either.

0.6.0

• Targeting by device (mobile / tablet / desktop) and country (ISO codes).
• HTML import: drag-and-drop dropzone + sandboxed iframe preview before submit.
• Visitor device classified from User-Agent; country pulled from Cloudflare/Kinsta CF-IPCountry header (and similar X-* headers), with a abtest_visitor_country filter for custom geo plugins.
• Targeting check happens server-side before any cookie is set or impression logged — out-of-target visitors fall through (no variant assigned).
• Admin/bot bypass mode is exempt from targeting so preview is independent of the previewer’s device/country.

0.5.0

• Multi-variant tests up to 4 variants (A/B/C/D) with equal split (1/N each).
• Stats engine supports pairwise comparisons vs baseline + Bonferroni-corrected alpha.
• Schema migration v1.2.0 — auto-backfills _abtest_variants from legacy control_id/variant_id pair.
• Admin form: dynamic variants list (add/remove rows up to MAX_VARIANTS).
• Experiments list: variants stacked vertically per row with lift + 95% CI vs baseline.
• CSV export extended with per-variant + pairwise columns.
• REST API stats response now includes variants, comparisons, baseline, best, alpha.
• Back-compat: legacy control_id/variant_id accessors and meta still work; legacy A/B keys still in compute() output.

0.4.0

• URL-decoupled experiments — test_url independent from variant pages.
• State machine (DRAFT → RUNNING → PAUSED/ENDED) with Resume = duplicate semantics.
• Baseline mode (Variant B optional) and auto-downgrade on URL conflict.
• Replace running atomic swap action.
• HTML import → Blank Canvas template (zero WP wrapper).
• Per-URL tracking scripts (Adwords, FB Pixel, Lemlist, etc.).
• Cache bypass (universal Cache-Control headers + WP Rocket + LiteSpeed + Kinsta detection).
• Google Analytics 4 integration (Measurement Protocol).
• Generic webhook integration (Zapier, Mixpanel, Segment, Slack, n8n) with HMAC.
• REST API GET /wp-json/abtest/v1/stats with Application Password auth.
• 95% confidence interval for the lift, date range filter, Chart.js timeline.
• GitHub Actions CI (PHP 8.1/8.2/8.3 matrix) + release workflow + Dependabot.

0.1.0

• Initial MVP — page-level A/B tests, internal tracking, cookie split, basic stats.