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All older add-ons can't install because they are corrupt?

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I'm using Firefox v126. I'm searching through the add-ons trying to find a few that I like and most don't work with my older version of Firefox. So I click into the version history of the add-on and find an older version of the add-on that will work with the version of Firefox I am running. Except... I click it and I get:

"The add-on downloaded from this site could not be installed because it appears to be corrupt."

say what? ok maybe a fluke, so I click on through, older version, older version, still old version. All give me the same error. Okay, maybe its just the add-on, no, its literally any older version of any add-on.

No way all those versions of add-ons are "corrupt." I can download the .xpi, rename to .zip and view the contents. Anyone run into this particular problem before and if so, how did you fix it? I'm keen to keep v126 of Firefox and would like to use the add-ons that I like to work with it.

I'm using Firefox v126. I'm searching through the add-ons trying to find a few that I like and most don't work with my older version of Firefox. So I click into the version history of the add-on and find an older version of the add-on that will work with the version of Firefox I am running. Except... I click it and I get: "The add-on downloaded from this site could not be installed because it appears to be corrupt." say what? ok maybe a fluke, so I click on through, older version, older version, still old version. All give me the same error. Okay, maybe its just the add-on, no, its literally any older version of any add-on. No way all those versions of add-ons are "corrupt." I can download the .xpi, rename to .zip and view the contents. Anyone run into this particular problem before and if so, how did you fix it? I'm keen to keep v126 of Firefox and would like to use the add-ons that I like to work with it.

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