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Preview of Word Replacer III

Word Replacer III by Khizar Rehman

Change your world one word at a time.

Available on Firefox for Android™Available on Firefox for Android™
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About this extension
Find and replace text automatically on any website you visit. Whole-word matching, rule groups, and regex support.

Word Replacer III automatically finds and replaces words or phrases on any webpage as you browse — no manual editing, no copy-pasting into another tool. Set up your rules once, and they apply every time you visit a matching page, including on sites that load or update content dynamically.

It started as a simple find-and-replace tool but has grown to handle the cases that trip up most extensions like it: matching whole words only (so a rule for "man" won't fire inside "management"), catching text that's split across bold or highlighted formatting, and staying fast even with thousands of rules active at once.

Key Features:
- Simple, RegEx, and Swap rule types, with Maintain / Override / Title / UPPER / lower case handling
- Whole-word (Isolate) matching, so short words don't accidentally match inside longer ones
- Cross-Element matching for text split across bold, highlighted, or styled spans
- Optional bold highlighting per rule, so a replaced word never gets mistaken for the original text
- Restrict any rule to specific sites, or apply it everywhere
- Organize rules into named groups you can toggle on or off together
- Search, sort, and duplicate-detection tools for managing large rule lists
- Live test field to preview a rule before saving it
- Export and import your rules as a backup, or generate a shareable link to send your whole list to someone else
- Dark and light themes

Common Uses:
- Cleaning up awkward phrasing or inconsistent names on machine-translated fiction and manga/manhua reading sites
- Language learning — swap in translations as you browse, with optional bold highlighting so you always know what's been changed
- Standardizing terminology across a site for work or study
- Personal reading preferences — swap words, censor terms, or adjust tone as you browse
- Accessibility and readability tweaks

Word Replacer III runs entirely in your browser. Your rules are stored locally and are never collected or sent anywhere, except when you explicitly choose to generate a share link for your own list. Free, with no ads.
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Permissions and data

Required permissions:

  • Download files and read and modify the browser’s download history
  • Access browser tabs
  • Access your data for all websites

Optional permissions:

  • Access your data for tinyurl.com

Data collection:

  • The developer says this extension doesn't require data collection.

Optional data collection, according to the developer:

  • Technical and interaction data
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Version
3.0.2
Size
175.1 KB
Last updated
2 days ago (Jul 4, 2026)
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Custom License
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