css, cap dropdown menu size dynamically

[michaelmicheal]

In this PR: #28561, I capped the dropdown menu size to 300px and made it scrollable past there. Instead, we should cap it at 85%.

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[uranusjr]

Would it be a good idea to use min here? 85vh can be quite long in some situations.

[j-martin]

In this case, the 85vh is only ever reached if the menu items count is significant enough. Prior to #28561, the menu could be much longer than the browser viewport (so > 100vh). With this in mind the change here is better than the current behavior.

If I interpret your suggestion properly we'd have something like min(85vh, 500px). As a users, I would rather have 85vh so I can see all the menu items if they fit in my viewport.

For context, we programmatically generate menu items to different projects (dag bags) and there can be a lot of them: