Is there a thing like good extensions and bad extensions on firefox. I mean, I don’t want to know about privacy and security of extensions right now, but does some extensions slow down the performance of firefox more than other extensions?
Also, how to distinguish these extensions from others? Does size of the extension matter? i.e., if the size of the extension is higher does that mean it’s eating more resources or will eat more resources.
Does a good extension run on all pages or only on the pages it’s needed? Is there a better way to handle extensions? Maybe disable some extensions which are not in use, idk!
Everything a computer does uses resources so every extension will have some performance impact, though you usually won’t notice the difference from any one extension. As a general rule of thumb, the more an extension does the more resources it needs and so the bigger the impact. Some extensions free up additional resources (eg by blocking ads or trackers) which may also result in a net performance gain dependant on the page you’re viewing.
A large extension on disk doesn’t necessarily use more memory and CPU time than a small one, but it is more likely to. The only reliable way to tell which extensions are resource hogs is by benchmarking them.
Disabling extensions not in use is a good idea, though personally I’d uninstall them instead.