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

  • 2 Mbohovái
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  • Mbohovái ipaháva benjaminleo174
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benjaminleo174
benjaminleo174

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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TyDraniu
TyDraniu
  • Top 10 Contributor

This is because the root certificate of your version of Firefox expired on March 14, 2025. You need at least Firefox v128 to be able to install add-ons.

Moreover, it's strongly not advised to use a year-old version due to security reasons.

benjaminleo174
benjaminleo174 Porandu apoha

I choose 126 to avoid some of the later features in the newer versions of Firefox. Do you know offhand if 128 contains any of the AI features in the later versions? How about whether or not updating the root certificate with a newer one is an option in Firefox?

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