bottom_whitespace: Show buttons to navigate to next unread narrow.

[amanagr]

This will allow users to easily navigate unread content and increase use of n and p hotkeys.

Fixes #18728

[alya]

A few comments from playing around with this PR:

1. The tippy tooltips are too invasive -- they pop up quickly, are very noticeable, and the user generally doesn't need them. Can we switch to regular tooltips, the way we have for the "New topic" and "New private message" buttons? I think those will be significantly less in the way.

2. It annoying to have the button jump around depending on how many messages are in the topic you just navigated to. You really want it to be consistently in the same place if so that you can keep clicking it without having to move the mouse up and down. Can we figure out a way to place it just above the compose box even if the topic only has a message or two you are looking at?

3. I don't love how the buttons look, though I do appreciate that the aren't as bright as the initial version. Perhaps we should discuss in #design?

4. Currently, in the interleaved stream view the buttons are not shown but the n key works. Unless it's too complicated to show the buttons from a technical perspective, this probably merits a #design conversation as well.

Sorry I missed this PR earlier!

[alya]

I just had the thought that we should make sure something reasonable happens if you're viewing a stream you aren't subscribed to, which has a "Subscribe" button in a similar location.

[alya]

Also, for visual consistency, we should probably have these buttons look the same/similar to the "Subscribe" button.

[timabbott]

I suppose we can update this now that we've merged the Spectators version of this feature?

[amanagr]

Yes.

[amanagr]

[amanagr]

@alya FYI this is ready for your review after you are free from 5.0 work.

[timabbott]

I'm test-deploying this on chat.zulip.org.

[andersk]

The template language is called Handlebars, not “handlebar”.

I just saw this button show up at the bottom of the All messages view with no unread messages, so it may not be getting updated at all the right times.

[timabbott]

@amanagr can you update this to address the above feedback and post a summary of its status? I'd like to try getting it deployed on chat.zulip.org again.

[amanagr]

Rebased.

I just saw this button show up at the bottom of the All messages view with no unread messages, so it may not be getting updated at all the right times.

Fixed. Thanks!

[timabbott]

I merged the first commit, and will be deploying this on chat.zulip.org shortly.

[zulipbot]

Heads up @amanagr, we just merged some commits that conflict with the changes you made in this pull request! You can review this repository's recent commits to see where the conflicts occur. Please rebase your feature branch against the upstream/main branch and resolve your pull request's merge conflicts accordingly.

[timabbott]

Removing chat.zulip.org review, since I think the next step for this is to try an alternative design for where the button goes.

One option that would at least be cheap to try is just putting "Next unread topic" in the left sidebar under "Drafts" and see how that works.