Stick to end of files and chats when someone else is adding content

[novoselt]

Current situation:

• scroll to the end of a long enough markdown file or chat
• it is fully visible, even with some blank space beneath
• now if someone else is adding to the bottom of that file or chat, the file scrolls a little bit up, with possibility of hiding even existed content, AND I do not see the new stuff!

What I would like to have: if I am already at the very end of the file, keep me at the very end even if the file grows!

I want to see new chat messages right away and if somebody is adding extra notes at the end, I also want to see them right away.

[williamstein]

To me this request is very vague. What's the actual implementable algorithm you want? E.g., "if I am already at the very end of the file, keep me at the very end even if the file grows!" isn't well defined. And "I want to see new chat messages right away and if somebody is adding extra notes at the end, I also want to see them right away." -- there are huge number of situations that can occur and defining any of that in terms of line numbers, (possibly multiple) cursor positions, etc., is not easy or clear. I could list dozens of "but what if..." in response to the scenario you describe.

Also, what exactly do other colab editing environments do in the situation you describe? Consistency with user expectations is important.

[novoselt]

It is clear in my head ;-)

"I am at the end of the file" means that there is no portion of the file which is not visible at the bottom. Is it easy to detect? E.g. this means that either there is no scroll bar because the file fits entirely on the screen, or there is a scroll bar and it is at the lowest possible position.

My request is: if in the above situation the file is changed by someone else instead of me actively editing it, keep it - either the whole file on the screen (which is of course already done) or set the scroll bar to the lowest possible position after the update.

The result: if I am just keeping an eye on the chat (or other type of file), I will see new messages as they appear, even if there are several pages of them over time. I think this is how most chats operate.

The only subtle point to me is dealing with my own cursor - if I am typing something, I definitely don't want any scrolling to happen at all. If I made a long enough pause (10 seconds?..), then I am OK if it scrolls away, but when I start typing it should bring the relevant position into the viewing window right away or completely forget it and require manual positioning of the cursor. Some systems do allow you to type something into a place which you do not see and it is extremely annoying since it is rarely (never?) intentional.

[williamstein]

The result: if I am just keeping an eye on the chat (or other type of file), I will see new messages as they appear, even if there are several pages of them over time. I think this is how most chats operate.

What if I am carefully reading the last message and a new message appears? Suddenly the whole chat/document jumps and I'm disrupted right in the middle of what I'm reading. My point is just that these rules you're thinking about are very much not obvious... There's many non-obvious what ifs like this. In my experience, every time I tweak anything about "how the document updates when merging it upstream changes" there's a bunch of surprising ways it is annoying. Overall, I've found that the most stable rule is to do the exact opposite of what you suggest, which is to keep things as stable as possible. That's why any change like you're suggesting needs to be really carefully thought through.