Some extensions after Firefox upgrade do not install the workaround.
① due to the version cause of the installation problem, you can use compression software (WinZip, WinRAR, etc.) to open the. xpi file, find INSTALL.RDF in it and open it with editing software (such as Notepad), then find < em:maxversion>, Increase the numbers that follow, such as changing the 0.9 to 1.5.0.*. And then repackage it again.
② installation Nightly Tester Tools extension, which allows you to install extensions that are incompatible with the Firefox version number.
Note: ① the above method does not guarantee that all incompatible extensions will work properly, and it is recommended that you wait for a new version of the extension to be released. ② When you upgrade an extension, it is best to uninstall the original extension and then install the new version.