Hi djdanieu, I'm not sure what's happening there. Can Firefox successfully retrieve the file if you use this method:

right-click the Install button and choose Save Link As...

Or do you get any new error message?

Yes, it defaults to save as XPInstall Install. here is the file path for ublock orgin ublock_origin-1.20.2-an+fx

i just tried to do the install add on from file, and nothing happened. No progress bar or indicator popped up.

Okay, that's very odd. Could you check for error messages in the "Browser Console" that might be related to this problem.

You can open the separate Browser Console window using either:

• "3-bar" menu button > Web Developer > Browser Console
• (menu bar) Tools > Web Developer > Browser Console
• (Windows) Ctrl+Shift+j

Click the trash can icon at the upper left to clear the window, then switch back over to the Add-ons site and try the Install again. (Or try the Install from File on the Add-ons page.)

Then switch back over to the browser console window. Did Firefox log any errors related to that action?

More info on the Browser Console: https://developer.mozilla.org/docs/Tools/Browser_Console

not sure why this worked but i just switched from my admin account on the computer to check something else. On a user account the add-on installed fine.

Ill try to post the info you were asking about when I switch back to admin account.

Thanks for the effort!

Perhaps it is related to a change in how Firefox 68 starts up.

To protect against unwanted DLL injections and to better protect against zero-day vulnerabilities, a launcher process runs Firefox with medium integrity (similar to a standard user) even if your regular user has administrative privileges. This article has more information on the potential side effects: https://support.mozilla.org/kb/windows-administrator-launcher-process-error-fix

However, I don't understand why that would prevent installing an add-on?!

Have you turned UAC down to the minimum setting ("Do not Notify")?

I use Firefox 60.8.0esr which is a package in Debian 10.0 (stable).

I go to the page: https://addons.mozilla.org/en-US/firefox/addon/history-cleaner/?src=search

I click on "+Add to Firefox". A small box appears at the top. I click on "Add". It hangs. The browser console says:

"PopupNotifications._onButtonEvent: Button click happened before the window was focused"

The "Cancel" option in the box also fails.

Hi edcjones, thank you for the console text:

"PopupNotifications._onButtonEvent: Button click happened before the window was focused"

The "Cancel" option in the box also fails.

Unless something else happened to take focus away from that window to another window, that is a very odd error to get.

Did this problem start for you in the latest ESR release (July 9th+), or earlier, or more recently?

jscher2000 said

Hi edcjones, thank you for the console text:

"PopupNotifications._onButtonEvent: Button click happened before the window was focused"

The "Cancel" option in the box also fails.

Unless something else happened to take focus away from that window to another window, that is a very odd error to get.

Did this problem start for you in the latest ESR release (July 9th+), or earlier, or more recently?

I installed Firefox as part of an install of Debian 10. The package is

firefox-esr (60.8.0esr-1~deb10u1)

The bug also occurs for:

https://developer.mozilla.org/en-US/do/Web/API/Notifications_API/

edcjones said

jscher2000 said

I installed Firefox as part of an install of Debian 10. The package is firefox-esr (60.8.0esr-1~deb10u1) The bug also occurs for: https://developer.mozilla.org/en-US/do/Web/API/Notifications_API/

The URL has an extra "/" at the end. It should be:

https://developer.mozilla.org/en-US/docs/Web/API/Notifications_API/Using_the_Notifications_API

Hi edcjones, I don't know why those drop-down panels are not working for you.

Could you test in Firefox's Safe Mode? In its Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, any userChrome.css/userContent.css files, and some other advanced features to help you assess whether these are causing the problem.

You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" Help button > Restart with Add-ons Disabled
• (menu bar) Help menu > Restart with Add-ons Disabled

and OK the restart.

A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Any improvement?

No change.

I have found _more_ things that do not work:

1. Click "Help", then click "Troubleshooting information". A few lines down is a box that says "Open Directory". Nothing happens when I click on the box.

2. Go to the Refresh Firefox page at:

https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings

There is a box saying "Refresh Firefox". Clicking on the box does nothing.

Does Firefox-esr ( Debian package 60.8.0esr-1~deb10u1) restrict what a user can configure?

Try the Firefox version from the official Mozilla server if you currently use a version from the repositories of your Linux distribution.

• https://www.mozilla.org/en-US/firefox/all/

The original problem I had with the notification window for the add-on "History Cleaner" suddenly went away. The "History Cleaner" page says that it was last updated on August 9, 2019 which is today. There may be a bug in the add-on updating process.

I still have the other problems.