Issue with appending objects

I’ve been using Blender for about a year now, and I’m just now having this incredibly strange and frustrating problem. I must have accidentally turned on some weird setting or something, and if so, I’d like to figure out how to turn it off and fix all the hell that its caused. The first thing I noticed with this is that sometimes when I append something, there’s a light blue outline around it instead of the usual yellow/orange. It says its in object mode but I can’t switch it to any other modes, and the objects can’t be moved or changed. Normally at this point I delete the objects and keep trying until its normal, but at some point I made the stupid mistake of finding a way to work with it. I think it was a button next to the object name in properties panel that seemed to make the object normal. But I noticed as I animated that there were still values I couldn’t change and I couldn’t duplicate some of the object’s keyframes in the dope sheet. There were also a few unusual crashes as I was animating, it somehow saved all the animation except keyframes on the imported objects. I kind of ignored it and worked around it as it continued to play hell with me while I was animating, until I finally finished. Now it seems that there are some materials on the objects that still have frozen values, and I can’t fix most of them. This wouldn’t be a problem, but objects with these materials attached show up invisible in Unity. It seems that this would be easy enough to fix by just creating new materials in place of these, but somehow if I do this and save the project, when I open it again they’re still there. I’m starting to think it just isn’t saving at all. I’ve also tried saving to a separate file.

Is it possible that you tried to append a linked object?
So, if your file is file A, you appended an object from file B, which does not really belong to file B, but is linked into file B from file C?

What colour does the outline of that object have in file B? If it is also blue, the file is linked into B.
You should in the future either make sure to only append the “original” local object (in my example: from file C). Or - after the fact - select the “appended linked” object in your file A and hit L to make it local.

Yeah, I just figured out where I went wrong. I’ve been using an on screen keyboard that covers up the link/append buttons on the menu, and I’ve actually been clicking link instead of append. But it seems pressing L does fix it, so thanks for the help.