Improve visibility of composer

[nadonomy]

We've seen in a user test session someone squinting and saying they couldn't quite see the composer to be able to send a message.

Related issue: https://github.com/vector-im/internal-planning/issues/24

[SimonBrandner]

This is partially related to #16304. The unprofessional mock up linked there could be an option

(IIRC, I've already discussed this with someone from the design team but both of us seemed to have forgotten about it :D )

[niquewoodhouse]

Using a 1px border of groupFilterPanel-bg-color on composer and room header

Using a 1px border of input-border-color on the timeline with groupFilterPanel-bg-color on the room header

It's a bit hard to tell from still images above what colours are good, so it might be worth having a netlify to test with but I believe those are the two best colours we have for this job (from my limited knowledge of the theme colours)

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Part of the reason people maybe aren't able to find the composer is the use of avatars to the left of the composer, while they're scanning for an input field. These kind of changes are maybe a bit bigger than papercuts.

[t3chguy]

@niquewoodhouse all above options are feasible, the composer previously had such a border and it was removed by Nad iirc, so would be good to double-check the intent there

[SimonBrandner]

I like the two latter options though I find them a little claustrophobic. I realize making the composer a bit higher would take up space though I think a few pixels might be worth it

[niquewoodhouse]

...the composer previously had such a border and it was removed by Nad iirc, so would be good to double-check the intent there

@nadonomy would you mind briefly confirming why the border was removed, if it's ok to add one again?

I'd also be interested in hearing if we may remove the avatar next to the composer - to match the latest composer work on mobile.

Thanks

[reivilibre]

I think this is basically the same issue but for different reasons, but I struggle to distinguish actual messages from the composer sometimes. It's usually when I've been thinking about what I'm writing, drop it for a second and come back, I can't tell which part of the text belongs to a sent message and which belongs to the composer.

Presumably the above ideas will sort this out as well. :)