HunchBluntley: For future reference, there's a URL-based workaround for the "links from reply quotes don't work properly in very long threads" problem. Instead of using the URL that links directly to the target post (or tries to), use the URL of the page of the thread that that post is on, and edit the link to add #p_b_[number] (where [number] is the target post's number in its thread) to the end of the link's URL, immediately after the page number.
It's a bit kludgy, but it works far better than doing it the normal way for anyone clicking your link in such a situation. :)
Example:
https://www.gog.com/forum/general/the_what_did_just_update_thread/page1083#p_b_21663

(I'm not sure how many posts a topic has to have before the issue that this works around rears its head, but I think it's safe to say that the "What did just update?" thread qualifies a few times over. :P )

muntdefems: Thanks for the tip, I wasn't aware of that method.

Unfortunately, it will only work for people that has the same posts-per-page setup as you do (e.g. for me the "What did just update?" thread only has 435 pages right now). :P

HunchBluntley: It would seem that a side effect of how they fixed it is that topics with low-rated OPs are no longer "auto-dimmed" in the topic list. (Which I'm fine with, if that was the cost of making the primary use of the "dimmed thread" mechanic work properly again.)

Cavalary: Would this mean you confirm the issue too?

HunchBluntley: [...] [W]hen searching keywords in the nav bar that are only relevant to one or more movies, and not to any games, the movie results don't show up automatically. One has to click the "# Movies" button to the right of the search box to get the actual results, even if there are no game results, and thus no "# Games" button. This is made extra confusing by the huge, white results box that says "No results found" (yet it will still contain a "Browse all movies" button that will take one to the movie section of the catalogue page, where everything displays normally and is searchable in the "local" search bar there...not that, once on that page, one needs to search, given that all movies on GOG currently fit on the one page :) ).
I can't imagine why this would be the intended behavior, so this should probably be fixed so that, if there are 0 game results, but at least 1 movie result when searching from the nav bar, the dropdown search results box will automatically select the movies category and display the relevant results.

On a final note, [...] the link to "All games for Linux" (hover over "Store" in the nav bar -> hover over "Browse all games" at the bottom of the resulting dropdown -> click on the rightmost box in the resulting popout) is rather outdated: the URL "system" flag is missing ",lin_ubuntu_18", the addition of which results in (currently) 16 more Linux results than the current link.
Which is just a longer, more helpful way of saying "All games for Linux" doesn't show all games for Linux. =]

HunchBluntley: [...] [T]he "System" filter for Linux 18.04 does absolutely nothing -- it doesn't even add the option to "Clear filters". All the other filters under that menu seem to work. [...]

muntdefems: For what it's worth, I've just received an email from GOG notifying me that some games on my wishlist are on sale. :)

Cavalary: So did I. Guess they fixed it.

toxicTom: Now the top search is broken... no results, no matter what I enter...