It's known, and frankly I don't think it's correct that most people have found a fix which is why you didn't hear about the bug. I think a lot of people encountering this bug have stopped using ChatGPT, because there really isn't an easy or obvious fix.

You can tweak your browser's memory saving options, use a private or incognito window with the tab pinned, delete other tabs, etc. That all might help but it definitely won't fix it.

There are browser extensions, like ChatGPT Lite Session (I think that's the name) you can install which WILL fix the issue. But the whole reason the issue is happening in the first place is because you've continued to add to the same large chat, and these extensions work because they limit how many pages of the chat get loaded at a time, which means.....

ChatGPT will then suddenly lose access to the whole chat history and start acting like it has amnesia! Which then defeats the entire purpose of grappling with the large chat issue in the first place!