Scrolling long threads is very tedious

Is it not possible to present a long thread in pages rather than one long scroll? It takes a long time to scroll down, refresh, scroll down etc.

I think it is not possible. But I find it much better than having to load a full page. If you want to jump somewhere in the thread you have a line on the right, you can click on it.

Is there a way to jump to the first or last post?

I have tried the scroll bar, but it kind of jumps about so I have to click it 3 times to get to the end. Usually when revisting a thread, you just want to go to the end to read the latest post!

I use page end keys of my keyboard,

That works !

Nevertheless having numbered pages is the standard way on most sites I have used

what I like in this ardupilot site format is that you can search for specifics in a single page, whereas in dyi drones site you will have to click yourself trough an huge number of pages

Yes, on top and bottom of the bar on the right you have dates. Those dates are the dates of the first and last post, if you click on it you’ll jump right to it.

Like I said above, getting to the end is pretty easy. Also, when you have unread posts in a topic and you enter it you should be redirected to the new posts.

Another method to navigate is to grab the bar on the right, you don’t need to click on it. You can grab, select the exact post/date you want to go to and it only jumps to the right post when you let go.