Can't reinstall add-on after downgrading
I'm trying to downgrade back to Firefox 56 after updating to Quantum, because there is no FTP add-on and I want to keep using FireFTP. However, now that I've downgraded, I cannot reinstall FireFTP because it's unsigned, meaning that not only can I not keep on the way I'd been keeping on, I also can't get all my login data from the FTP client in order to apply it to another client. When I try to install the .xpi from the developer's github, I get "Firefox has prevented this site from installing an unverified add-on."
How can I install this add-on, or failing that, at least get all my data from it?
Additional System Details
- Shockwave Flash 32.0 r0
- User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:56.0) Gecko/20100101 Firefox/56.0
On Friday, May 3rd, 2019, we became aware of an issue with Firefox that prevented existing and new add-ons from running or being installed. We are very sorry for the inconvenience caused to people who use Firefox.
Although the issue has been fixed on the recent version of Firefox, it may still take some time to get a working fix for the older (and unsupported) versions. There are some steps at the bottom of the blog post linked above to apply a hotfix to your browser.
Hope this helps.
Thank you, it seems like the studies are already enabled.
This extension was just released and should solve the problem :
Still the same response, I'm afraid :(
If it's not possible to reinstall the add-on, is there any way for me to recover the stored credentials?
Did you previously take any action to get the new certificate to replace the expired certificate?
Do you see the certificate in the Firefox Certificate Manager?
Are there messages in the Browser Console about this extension if you check this after a startup?
You can check in the Certificate Manager whether you have the new intermediate certificate installed. You can find it under the Authorities tab.
- Options/Preferences -> Privacy & Security
Certificates: View Certificates
Scroll down to see if you can locate this entry:
- Mozilla Corporation: signingca1.addons.mozilla.org
No, no previous action; I'm not familiar with how that works. This particular add-on is no longer in the add-on shop (it's FireFTP and needs to be obtained from the developer's git these days) but it had been working just fine before I updated. No console messages, I do see that Mozilla certificate.
The FireFTP extension isn't signed, so you would have to disable extension signing to be able to install this Legacy extension.
This pref sets whether honor extension signing and you would have to disable this security feature to be able to install this extension
- xpinstall.signatures.required = false
You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.
You can check for problems with the extensions registry files in the profile folder.
Try to to reset the extensions registry and rename extensions.json (extensionsOLD.json) and rename/remove previously used extensions files like extensions.ini and extensions.sqlite when present and rename/remove compatibility.ini in the Firefox profile folder with Firefox closed.
New files will be created when required.
See "Corrupt extension files":
If this didn't help then delete add-ons.json and possibly prefs.js in case there is a problem with preferences.
You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.
- Help -> Troubleshooting Information -> Profile Directory:
Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder
You are better off using the current Firefox and using a proper FTP client for anything FTP.
A FTP client to consider is the open-source FileZilla FTP client that has been around for a long time. It has no relation to Mozilla as some mistaken due to zilla in name.
Hello, sorry for the delayed response, I had some time off.
@cor-el I tried your suggestions of unchecking signing and of renaming the extensions and compatibility files; this was unsuccessful.
@James I'm trying to install FileZilla and having some trouble. Hopefully our IT can sort that out, but as I said earlier I'm still concerned that I may not be able to recover any of my logon data from FireFTP, even if I do need to begin using another FTP client. Any ideas for recovering my data from this application?
You can do a search in the profile folder for two files.
fireFTPsites.dat has most of the data, but not passwords.