Sorry that has happened. Most people just upgrade or take with out reading. Since doing a beta release it is imperative for you to read so know the bugs and features so that you can help by reporting things. If were on ver 56 before this in the Extensions/addons programs would have be listed as Legacy and not compatible with ver 57 and more so if went to the addon/Extension page for the program. Unfortunately there is not anything that can be done. I would suggest contacting the maker of your Extension and find out if anything is still left stored somewhere on the system in a file or folder that will put you together for ver 56 or lower. Should have a backup or system image file when doing beta releases. If you have one then use it to recover or try a system restore. G'Luck.

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