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Firefox for Mac

Firefox 55.0

  -  48.8 MB  -  Freeware

Sometimes latest versions of the software can cause issues when installed on older devices or devices running an older version of the operating system.

Software makers usually fix these issues but it can take them some time. What you can do in the meantime is to download and install an older version of Firefox 55.0.

For those interested in downloading the most recent release of Firefox for Mac or reading our review, simply click here.

All old versions distributed on our website are completely virus-free and available for download at no cost.

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  • Firefox 55.0 Screenshots

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    Firefox 55.0 Screenshot 1
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  • Firefox 55.0 Screenshot 3
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  • Firefox 55.0 Screenshot 5

What's new in this version:

- Export Screenshots 10.5.0 to Firefox
- Fix eslint warnings in about:webrtc
- Allow Flash to create Secure Socket connections
- Ensure pixels for Android dynamic toolbar snapshot get processed even if the toolbar is not visible so pending animations may run
- Backed out changeset 4488424e14ae for causing Bug 1377802
- Check if bookmarking UI is visible before anchoring bookmarking popup. This also avoids flushing when bounds checking the identity popup for visibility
- Disable frames() timing function using a pref on release/beta channels
- Part 3: Don't use restricting SIDs when running from a network drive
- Part 2: Add option to Windows chromium sandbox policy to not use restricting SIDs
- Part 1: Back out changesets 04edb03fb817 and d17ac655cc51
- Catch exception to handle creating media session fail. The crash reason is that our package name [1] is not the same as the name from packageManager's getPackagesForUid(uid) [2].Not sure what causes it and how it happen, but we can catch this exception first to avoid the crash
- Set CSP on freshly created nullprincipal when iframe is sandboxed
- Fix leak of nursery memory
- Only set user's SID in USER_LIMITED as deny only when not using restricting SIDs
- Disable H2 origin extension on Gecko 55
- Bump security preload information expiration dates to 2017-11-14 for Firefox 55
- Skip browser_toolbarbutton_menu_context.js for frequent failures
- Hold strong refs to elements when calling various functions that can run script
- Convert exception messages from the requests module before logging them
- Part 3: Require fallible Init method rather than infallible constructor when using fallible allocator
- Part 2: Deserialize StructuredCloneBlob in segments rather than a single large allocation
- Part 1: Initialize all members when using an inherited constructor
- Null-check result from GetTextRun in nsRubyBaseContainerFrame
- Add context-fill-opacity to back-large.svg
- Stop sending max-message-size
- Block D3D11 on more crashy nvwgf2um.dll versions
- Update follow-on search add-on to 0.9.1 - fix double reporting and fix case sensitivity
- Fix broken automatic HAR logs exported
- MutableBlobStorage always returns a temporary-file Blob if the size of data is greater than 1mb
- Change search settings redirects to General section of about:preferences
- Key cached manifest and locale data by add-on version
- Look for text run boundary based on transformed text when needed
- Nest ShellContext lifetime within JSContext
- Avoid null pointer deref
- Fix vertical scrollbar
- Post: remove unused code
- Guard against a nullable cursor
- Allow Adjust campaign ID to behave as OTA distribution
- Add reftest for verifying onVRPresentChange
- Don't honor the idle period during shutdown
- Add missing #include for MOZ_THREAD_LOCAL
- Support multi-line stub installer footer text
- Early return from timeline render if destroy was called
- Remove delay rendering add-on permissions popup header
- Part 2: Set initial tab title to URL's hostname until we know the actual page title
- Part 1: Add test for about: pages' initial tab titles
- repack betas are broken bc mock can't find python
- linux 55.0 repack betas are broken in comparing locales because due to missing python executable.r=aki a=testing a=jorgk
- Enable flash plugin preferences even when set to 'Never Activate'
- Sign the dummy webextension used in ts_paint_webext so that it doesn't run afoul of addon signing restrictions on Beta
- repack betas are broken bc mock can't find python, fix
- linux 55.0 repack betas are broken in comparing locales because due to missing python executable
- Enable flash plugin preferences even when set to 'Never Activate'
- Change app.update.staging.enabled preference to false on Windows to disable update staging
- Better check of the buffer size in WebSocket
- Request an even longer timeout for browser_noopener.js
- Manage TabGroup::IsBackground passively to avoid Runnable overhead
- repack betas are broken bc mock can't find python, fix
- Backed out changeset 68d491c00355 from bug 1329355 to temporarily fix bug 1372698
- Backed out changeset 318f1bcd336e from bug 1329355 to temporarily fix bug 1372698
- Tighten up mtime checking test_update.js