URL Sanitization

CleverKeys can automatically strip tracking and analytics parameters from URLs as they enter your clipboard history. Copy a link with utm_source=...&fbclid=...&aff_short=... attached, and the version saved to your clipboard arrives clean: just the URL you actually want to share. The feature uses the ClearURLs ruleset and supports your own custom rules.

Quick Summary

What	Description
Purpose	Remove utm_*, fbclid, gclid, aff_*, and other tracking params from copied URLs
Trigger	Runs when text enters the clipboard history (system copy event)
Scope	Clipboard only — typed text is never sanitized
Feedback	Silent — sanitized text replaces the original with no toast
Default	Off — all three rule toggles default to disabled (“Also clean system clipboard” defaults on, but does nothing until a rule toggle is enabled)
Access	Settings → Clipboard → URL handling

How It Works

When you copy text containing URLs:

1. The system clipboard change fires ClipboardHistoryService.addClip().
2. The full clipboard text is run through a URL detector (regex over the whole text — handles multi-URL and surrounding prose).
3. Each detected URL is matched against the active ruleset, which has ~200 providers like Amazon, AliExpress, Google, Facebook, Twitter, Reddit, plus a globalRules provider that handles the universal utm_* family.
4. Matching parameters are dropped; non-matching parameters are preserved. URLs containing literal quotes (AliExpress embeds JSON like pdp_ext_f={"order":...} in params) are captured whole, so the junk after the quote gets stripped too.
5. The sanitized text is what gets saved to clipboard history (and pasted from CleverKeys’ clipboard panel).
6. If Also clean system clipboard is on (the default) and something was actually stripped, the cleaned URL is written back to the Android system clipboard too — so a plain long-press → Paste in any app also gets the clean link.

Settings changes apply immediately: toggling any of these mid-session rebuilds the sanitizer without restarting the keyboard.

The Toggles

All in Settings → Clipboard → URL handling:

Toggle	Setting key	What it does
Sanitize tracking parameters	clipboard_sanitize_links_enabled	Master switch for the bundled ClearURLs ruleset. Strips utm_*, fbclid, gclid, per-provider trackers like AliExpress spm/scm*/aff_*/pdp_*, Amazon ref/tag, Reddit share trackers, etc.
Enrich embeds for sharing	clipboard_embed_enrich_enabled	Separate ruleset that rewrites social-media hosts for richer link previews (x.com → fxtwitter.com, reddit.com → rxddit.com, etc.).
Use custom rules	clipboard_custom_rules_enabled	Load your own ClearURLs-format JSON. When enabled, a Browse… button appears for picking the file via SAF.
Also clean system clipboard	clipboard_sanitize_system_clipboard	When a URL was actually cleaned, write the cleaned form back to the Android system clipboard so pasting in any app gets the clean link. On by default; inert until one of the rule toggles above is enabled.

[!NOTE] The three rule toggles are independent. Enabling “Enrich embeds” alone does NOT strip tracking parameters — you also need “Sanitize tracking parameters” on for the bundled ClearURLs rules to apply. If you previously enabled sanitization and saw no effect, double-check the master toggle is on.

Worked Examples

Standard tracking strip

Copy:

Check this out: https://example.com/article?utm_source=newsletter&utm_medium=email&id=42

After sanitization (master toggle on):

Check this out: https://example.com/article?id=42

utm_source and utm_medium matched the global utm_* rule; id did not match any rule and was preserved.

Provider-specific (AliExpress)

Copy:

https://www.aliexpress.com/item/12345.html?spm=abc&scm_id=xyz&algo_pvid=123&utm_source=share&keep=value

After sanitization:

https://www.aliexpress.com/item/12345.html?keep=value

AliExpress’s spm, scm*, and algo_pvid matched the provider’s ruleset; utm_source matched the global rule; keep matched nothing.

Embed enrichment

With Enrich embeds for sharing on, a Twitter link becomes a fxtwitter link for better Discord/Slack/Signal previews:

https://x.com/user/status/12345  →  https://fxtwitter.com/user/status/12345

This is a redirect rewrite, not a parameter strip. Rewrites ship for Twitter/X, Reddit, Instagram, TikTok, Bluesky, Pixiv, FurAffinity, and DeviantArt. A companion rule in the tracking ruleset strips the embed_host_url parameter from reddit.com and rxddit.com links (it leaks the embedding site) — so with both toggles on, a copied Reddit embed link comes out as a clean rxddit link.

Custom Rules

Toggle Use custom rules to load your own ClearURLs-format JSON. The format is documented at docs.clearurls.xyz — a providers object keyed by name, each provider has urlPattern, rules (regex per-param to strip), rawRules (regex per-URL substring to strip), redirections, and optional exceptions.

After enabling the toggle, tap Browse… to pick the file via the Android file picker. It’s copied into the app’s private storage at <app data>/url_rules/custom.substitutions.json. The custom rules are MERGED with the bundled ClearURLs rules (if the master toggle is also on), with custom providers added alongside bundled ones.

[!TIP] Common reason to add custom rules: a small domain you use frequently isn’t covered by the bundled ~100 providers. Write a minimal urlPattern + rules block for it. The bundled set updates with app releases; custom rules let you patch in coverage between releases.

What This Does NOT Do

• Doesn’t follow short URLs. bit.ly, t.co, etc. are not expanded — the rules can rewrite some short URLs to their long forms via redirect rules, but there’s no live HTTP resolution.
• Doesn’t run on typed text. If you type a URL with tracking params directly into a text field, it’s not touched. Only clipboard inserts (system copy events) trigger sanitization. (Autocorrect separately avoids URLs you type — see Autocorrect — but that’s a typing guard, not sanitization.)
• Doesn’t notify you. No toast, no badge, no log entry. Sanitization is silent. To verify it’s working, copy a known tracking URL and inspect the clipboard history entry (Settings → Clipboard → History).
• Doesn’t have per-provider granularity in the UI. You can’t toggle “strip Google only” — it’s all-or-nothing per ruleset. For fine-grained control, write a custom rules file with just the providers you want.

Troubleshooting

”I enabled the sanitizer but my AliExpress URL still has all the tracking junk”

Three things to check:

1. Is the master toggle on? Settings → Clipboard → URL handling → Sanitize tracking parameters must be checked. Enabling only “Enrich embeds” or only “Use custom rules” doesn’t enable the bundled rules.
2. Are the specific params in the bundled ruleset? AliExpress bundled rules cover spm (via the global rules), scm*, algo_*, gps-id, the whole aff_* family (aff_short, aff_platform, aff_request_id, …), pdp_* (including pdp_npi), utparam-url, ws_ab_test, btsid, mall_affr, terminal_id, gatewayAdapt, srcSns, and more. A param that still survives probably isn’t in the bundled set — add a custom rules file for it.
3. Did you copy the link, or paste a previously-saved one? Sanitization runs on the copy event. URLs already saved in clipboard history before you enabled the feature aren’t reprocessed.

”The sanitizer broke a URL I need”

If a domain’s urlPattern matches your URL but a rule incorrectly strips something useful, you have three options:

1. Disable the master toggle when copying that particular URL (suboptimal).
2. Write a custom rules file with an exceptions regex for that URL pattern.
3. Report the bundled ClearURLs rule upstream at docs.clearurls.xyz.

Configuration Reference

Setting	Key	Default	Range
Sanitize tracking params	clipboard_sanitize_links_enabled	false	bool
Enrich embeds	clipboard_embed_enrich_enabled	false	bool
Use custom rules	clipboard_custom_rules_enabled	false	bool
Custom rules file	clipboard_custom_rules_uri	(none)	SAF URI / local path
Also clean system clipboard	clipboard_sanitize_system_clipboard	true	bool

Related Features

• Clipboard History — Where sanitized URLs land
• Clipboard Privacy — Password-manager exclusions, sensitive-flag handling
• Text Selection — Swipe-to-select gestures

Technical Details

See URL Sanitization Technical Specification for the algorithm, ruleset format, and code references.