Can't use Firefox Add-on in new version of Firefox

I have made a few Firefox Add-ons, and used them in production, it worked for a few weeks.
But after Firefox has the new version 88.0(64-bit), I found I can’t use my Firefox Add-ons any more.
The issue looks like that all the Add-ons disapper from the toolbar, even I tried to custome toolbar, still I can’t see any of the Firefox Add-ons icons appear on the toolbar.
However, it is not totally disappeared, but hide somewhere in the double arrow icon.
However, the issue for my Firefox Add-ons is: I can’t launch it any more.
The only way to use my Firefox Add-ons is that I can use the un-zipped in Test Mode.
Let me know how to fix this issue.
I think the most important thing is how I can put the Add-On icon on the Firefox browser toolbar as in old version of Firefox. It is also true for another Firefox Add-on: “Privacy Pass”.
Please advise!