I just would like to see and read the " blue " threads .

News threads do get separated from others into a specific group, as you don't have to skim through everything for that.
Just be aware that only these are visible as on same page, so you still have to change pages for older ones.

Thank you, much appreciated.

Thanks for the fork, the grouping of news posts is a great idea!

Would it be possible to add another option to the various groupings that places them above the favourited threads?

Another idea that may be popular: Grouping delisting threads together. I think GOG's own topics tend to use the word delisting, but probably best to include the words delist, removal and remove just in case.
That together with an option to place the group above favourited topics should ensure they're fairly impossible to miss whether GOG stickies them or not (which is a polarising issue).

Surely it's possible, yet I'd like to know beforehand: doesn't collapsing whole favourited topics' section kinda achieve the same goal?

Not a problem, I can add a new grouping for that kind of topics as well, even make them the top one of them all.
But first I'd like to see a finalized verdict on how these topics will be announced in the near future.

About the keywords part, I intend to consider only "delisting" one, as others mostly will be wrongfully included in terms of false positive hits.

Almost, although I make such heavy use of the favourited threads that I forget the rest of the forum exists. I was mainly thinking it would be good to have the (hopefully empty most of the time) delisting group at the top so that when there is a delisting topic it really jumps out. If you don't think it's worth it then that's fair enough.

That makes sense. Delisting and delisted are probably specific enough but removal would probably get false positives as you say.

This thread seems to have settled on a policy, but it's hard to know if the naming will stay the same. Up until now I think all of the official threads have used the word "delisting" in the title.

GitHub
Script source Done. See if everything is there as it was expected.
I assume, most of these script managers should behave the same way, at least on part of executing the script.
But there could various discrepancies, so it'd better to test it out personally.

Seems to work amazingly, thank you so much! Hopefully this will keep me from missing any more delisting threads. :D

Just a small update on the delisting thread feature, it's mostly been working great but I just discovered this thread fell through the cracks: https://www.gog.com/forum/general/delisting_unreal_games_unreal_tournament_2004_ut_goty_unreal_2_the_awakening_special_edition/
My guess is due to the square brackets around the word delisting. Obviously the search sees "delisting" and "[delisting]" as different words. Is there anything that can be done to make it pick up on any word containing the component "delisting"? Maybe putting asterisks (i.e. wildcards) around it would do the trick?

The main problem here is that the script expects here to see "delisting:" part with semicolon in it as well, as that was my assumption what naming convention is chosen by staff around here.
At the moment I can see that it was renamed later to expected naming and it gets picked up properly right now. But if it will happen again, then maybe it would be better to just remove the semicolon part.

Ah yes, I see Sysia granted my request. Still, the colon is probably not necessary as I think picking up any thread with the word delisting somewhere in the title is ok. On the offchance a user makes a thread containing that word I think it would probably still be relevant. Thanks again!

GitHub
Script source Additional info:
- opening en masse might be blocked by a browser, tell it to allow popups;
- (x out of y) part means x - number of topics that will be opened on clicking (max to 15), y - number of all new relevant topics found;
- during openings oldest topics are prioritized first;
- clicking a link doesn't mark opened topics as read, reload the page to update topics' status.

Thank you.

Perhaps consider adding a configuration option whether to open in new windows or new tabs. Currently it opens in new windows for me, possibly because that is my default browser setting, but in this special case I would prefer it to be tabs; and using Ctrl+click doesn't help. Not very important --- just a nice to have.

In what way to open new links is a user preference of currently using browser, which can't be overridden by JS in modern browsers.
Maybe if this script was provided via an extension it could be done, but its completely different story.