Finding Addon/Extensions information

Using Tbird 68.8 and I am trying to diagnose an error message. Using the start with addons disabled fixed the problem temporarily but it is back now. So I opened the troubleshooting page and found several extensions I didnt install, including Amazon and Twitter. How do I find Info about these extensions and how do I remove them? I went to the Tools>addons page and only two are listed, Lightning and Send Later which I did install. Thanks for your time.

Twitter and Amazon are search engines.

You can see them listed under Tools > Options > General Default Search Engine.

I would disable the Send Later extension and see if the problem goes away.

OK thank you. It is not doing it right now . I will try your
suggestion if it happens again.