Seek bar extends underneath side panel(AV)

[LanieOkorodudu]

Description
The seek bar currently stretches underneath the “Contents” and “More Information” panels, which makes things look a bit messy.

Steps to reproduce

1. Play this AV manifest: https://iiif.io/api/cookbook/recipe/0064-opera-one-canvas/manifest.json
2. Notice that the seek bar extends underneath the ‘Contents’ and ‘More Information’ panels.

Expected behaviour
The seek bar should stay within the visible space between the side panels and not go underneath them.

Suggested fix
It would be great if the seek bar could be limited to the space between the panels, or if the layout could be adjusted so nothing overlaps it.

See attached screenshot showing the issue in Safari

See attached screenshot(Chrome, edge, Firefox)

[demiankatz]

@LanieOkorodudu, is this a new or existing problem? (Just want to double-check whether it impacts the current release candidate process).

Also, how does this relate to @jamesmisson's plans to change the way the side panels interact with the center panel? (I realize his work relates to Open Seadragon, but this issue seems to be related to equivalent behavior in the AV modules). Perhaps James can share some thoughts on this!

[LanieOkorodudu]

I believe this is an existing issue related to AV and should not impact our release candidate. This will be addressed separately as part of the AV work at the BL, @Saira-A please feel free to add any details if I’ve missed something.

[Saira-A]

@demiankatz Existing, it's been there since at least v4.2 but v3 is fine. As Lanie said we're working on AV stuff so are just opening issues as we find them