Update to 2.53.11
Default version of Firefox for the User-Agent string has now been changed to 68.0 . This should provide better compatibility with modern sites. The value can be changed in Preferences-->Advanced-->HTTP Networking .
Besides that, an alternate site-specific override machanism is now activated. (The idea comes from Waterfox-Classic project). The file ua-update.json in the application dir is now additionally used for a list of overrides. You can copy it into your profile and edit if needed (be careful with format.) The "general.useragent.override.*" way continues to work and takes precedence. The new mechanism can be toggled by "general.useragent.updates.enabled" prefs (in about:config).
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