Alt+Left/Right was implemented to work in Firefox, as that was the only browser where the issue from this page could be reproduced.
Does not work on the main forum page in offline mode. It works on the main site page and in forum threads.
Upon first visiting the site or forum (offline), all threads appear as if they have new messages, highlighted in bold. Only after an hour or more (today, three and a half hours have passed and all threads still haven't become "all read") do all threads become normal, while threads with new messages are highlighted in bold.
It seems to me that on such a first visit (without browser history), all threads should immediately appear normal (all read), and only become highlighted when a new message appears.
When I enter a forum thread and it jumps to a new message, after reading it, I decide to reply. I enter my data, and in that thread, I get thrown to the very top, instead of staying on that message. I have to scroll down the page every time. And when logging out of my account after leaving a reply, it also throws me to the top of the thread, rather than staying where I left the reply — in case there's an error and I need to edit. I have to scroll down.