Win10 press alt to pop up the menu bar, select tools - add-ons
Add attachments manually
When using the Firefox browser in the computer system, we often add various plug-ins to improve the browser's use functions. However, some users add a plug-in in the Firefox browser, but it prompts "This add-on cannot be installed because it is not verified". For such a problem, we may wish to refer to the following methods first to see if the problem can be solved.
What should I do if the computer adds a Firefox browser plug-in and prompts that the add-on cannot be installed without verification
1. Open the Firefox browser, enter about:config in the address bar and press Enter;
What should I do if the computer adds a Firefox browser plug-in and prompts that the add-on cannot be installed without verification 1
2. It may prompt "May invalidate the quality assurance", just click "I promise to be careful";
What should I do if the computer adds a Firefox browser plug-in and prompts that the add-on cannot be installed without verification?
3. Find xpinstall.signatures.required, right-click to select "Switch", and change it to false;
What should I do if the computer adds a Firefox browser plug-in and prompts that the add-on cannot be installed without verification 3
4. After switching, restart the browser, and then directly drag the XPI plug-in into the window to install it.
When the computer adds the Firefox browser plug-in, it prompts "The add-on component cannot be installed because it is not verified", then you can use the above method to set up and install it successfully.