Mac text replacement not working in Firefox
Firefox only added macOS Text Replacement support in version 136, and it still skips some fields. What to update, the about:config setting, and what to use.
The short answer
For about ten years Firefox didn't support macOS Text Replacements at all. Support arrived in Firefox 136, released in March 2025, so first make sure you're on 136 or later. If it still doesn't work, check that the widget.macos.automatic.text_replacement preference in about:config is set to true. Even then, Firefox skips email and URL fields and has no Substitutions menu. For full coverage, use a text expander like Espanso or Raycast.
A short history
The Firefox bug "Mac 'text replacement' feature does not work in forms" was filed in 2015. The reporter's example was typing omw and a space and expecting "On my way!" Code for it landed in July 2024, in the Firefox 130 cycle, but it shipped switched off behind a preference.
Mozilla turned it on for everyone in Firefox 136, first released on 4 March 2025. The release notes say: "Added support for the text replacement feature in an input field on macOS. Web content can enable/disable this using the HTML autocorrect attribute."
That explains most of the conflicting advice online. Forum posts from before 2025 say Firefox doesn't support text replacements at all, and for the version those people ran, they were right.
Step 1: update Firefox
If you're on a version older than 136, updating is the fix. Check your version number, update if it's below 136, and then test a shortcut in a normal text field, such as a site's search box or a comment form.
Step 2: check the preference
The feature is controlled by a preference called widget.macos.automatic.text_replacement. In current Firefox source code, its default value is true. If it was changed at some point, for example while someone tried the feature before it shipped, it may still be off.
- Type
about:configin the address bar and press Return. - If Firefox shows a warning page, accept it to continue.
- Search for
widget.macos.automatic.text_replacement. - Make sure it's set to
true, then restart Firefox.
Where it still won't work
Even on a current version with the preference on, there are gaps. These are documented, not guesses.
- Email and URL fields. An open bug, "Firefox doesn't support macOS text replacement shortcuts in email and URL fields", says Firefox expands shortcuts in text and textarea fields but not in email or URL inputs. Safari and Chrome handle all input types except passwords.
- No Edit > Substitutions menu. Most Mac apps let you toggle text replacement from the Edit menu. Firefox doesn't have that menu yet. The request is tracked as "Add substitutions menu into Edit menu" and is still open.
- Sites that opt out. As the release notes say, web pages can turn the feature off with the
autocorrectattribute. Firefox won't override that. - Web apps with their own editors. Some rich editors handle typing in their own way. Google Docs is the best-known case, covered in Mac text replacement not working in Google Docs.
Rule out macOS itself
If shortcuts fail in Firefox and also in TextEdit, Firefox isn't the cause. Try adding a temporary text replacement in System Settings > Keyboard > Text Replacements and then deleting it. Guiding Tech and an Apple Community poster both report that this brings the rest back. More checks are in text replacements stopped working after a macOS update.
Options that cover every field
If you type a lot of email addresses or URLs, the field gap will annoy you. A system-wide expander doesn't use the macOS substitution feature, so Firefox's field rules don't apply to it.
| Tool | Price | Notes |
|---|---|---|
| Espanso | Free, open source | YAML config. Install from the Mac page or with Homebrew. |
| Raycast | Free for personal use | Snippets expand by keyword in any text field. |
| Alfred Powerpack | £34 one-time | Snippets with auto-expansion. |
| Typinator | $49.99 one-time or $29.99 a year | Imports from TextExpander, aText, Alfred, Espanso and PhraseExpress. |
Espanso doesn't work in password fields either. Its docs explain that macOS Secure Input blocks it there, and that a password manager can leave Secure Input stuck on.
Thunderbird
Thunderbird shares Firefox's engine. A bug where text replacement misbehaved in the compose window was fixed in the 140 branch, so update Thunderbird if you see it there.
Summary
- Update to Firefox 136 or later.
- Check
widget.macos.automatic.text_replacementistrueinabout:config. - Expect no expansion in email, URL and password fields, or on sites that opt out.
- Use a system-wide expander if you need those fields covered.