Resources on bootstrapped extensions

[vannilla]

Hello.
I'm trying to develop a bootstrapped extension, but I'm having issues when dealing with UI.
Classic overlays would definitely be better when adding UI elements, but in this case having an overlay is a bit too inflexible.
Anyway, the problem is that after restarting the browser, the UI elements are not added to the toolbar I placed them in.
I tried looking at spme other extensions, but I don't understand anything (or trying to do like them doesn't work).
Since I'm looking for help on this matter, I thought I'd also ask for other resources, if any.
Are there any guides and/or easy-to-read extensions, so that it's possible to have a better grasp of the whole bootstrapping thing?

[JustOff]

Unfortunately, I'm not aware of existence of such guides. In my extensions I use a method I discovered while studying other add-ons. I think the simplest one is Greedy Cache. Its source code does not contain comments, but feel free to ask questions if you need to clarify anything.

[vannilla]

Thanks, I'll check it out.
Would it be possible to add an explanation of that method to the Pale Moon wiki?
Even just two lines to explain the basic idea.

[JustOff]

Sorry, I'm too lazy for this, maybe it will happen sometime when I have inspiration and a lot of free time, but I can't promise. In the meantime, try to go through the example and ask questions here.

[vannilla]

I understand, thanks anyway.
I've read the linked example, studied it a bit, and by following the same pattern I got what I wanted, so I achieved half of what I was looking for in this thread (the other being other resources on bootstrapped extensions in general, since MDN is relatively bare).