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Preview of Form Field Find & Replace

Form Field Find & Replace by Itwerx

Find and replace text across every editable form field on a page - plain text, whole word, or regular expressions with backreferences. Preview before you replace, undo after, and it remembers your previous searches along with the settings they used.

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Preview exactly what a pattern will do - including backreferences - before touching a single field.Previous searches come back with the settings they used, not just the text.Plain text, whole word, or regular expressions. Count first, undo after.
About this extension
Find and replace text across the editable form fields of whatever page you are looking at.

It works on text inputs, textareas, and rich-text (contenteditable) editors, and it can reach inside same-origin iframes and open shadow DOM. Plain text, whole-word, and full regular expressions with backreferences ($1, $2, $&, named groups) are all supported.

WHAT IT DOES

Preview before you commit. A live preview shows exactly what your pattern would produce, including backreference substitution, before a single field is touched. Count matches tells you how many fields would change.

Undo. One level, applied through the same path a real edit would take, so frameworks notice. If a run would exceed the undo limit you are warned BEFORE it starts, not after.

Remembers your searches - with their settings. Click the Find or Replace box and pick from your previous searches. Each remembered entry restores the find text, the replace text, all four option checkboxes and the field-type selection together. That matters: a remembered pattern recalled without its "regular expression" flag would be searched for literally and quietly report no matches.

Choose what it touches. Thirteen field-type checkboxes let you restrict a run to, say, only textareas, or only date fields.

WHAT IT WILL NOT TOUCH

Password, hidden and file fields are never read or written - they are excluded before matching even runs, not filtered afterwards. Neither are disabled, readonly or aria-readonly fields: those are the page telling you the value is not meant to be edited.

Number, date and time fields are checked after writing and rolled back to their original value if the result would be invalid, rather than being left blank. Those are reported as skipped so you know the run was not fully applied.

NOTHING LEAVES YOUR BROWSER

No network requests of any kind. No telemetry, no analytics, no crash reporting. Your searches are remembered in local browser storage only, never synced, and a Clear history button removes them.

PERMISSIONS

It asks for exactly three: activeTab, scripting, and storage.

There is deliberately no host permission. The extension has no access to any page until you click its toolbar button on that tab, and that access does not persist across navigation. It is not running in the background on every site you visit, because it cannot be.

KNOWN LIMITATIONS

A deliberately pathological regular expression can still freeze the tab; there is a per-field time budget, but JavaScript cannot interrupt a regex already running. Closed shadow roots and cross-origin iframes are unreachable by design. Editors that do not use real form fields - canvas-based ones, or CodeMirror-style editors that keep their state elsewhere - are not supported.
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Version
0.6.0
Size
55.31 KB
Last updated
12 days ago (Sep 30, 2026)
Related Categories
  • Search Tools
License
MIT License
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