Allow hiding of "Sidebar extensions" when using vertical tabs

[ForwardUntoDawn]

When using vertical tabs, some extensions (such as BitWarden) are shown at the bottom of the sidebar and cannot be hidden.  This is despite having BitWarden in my menu bar, for example.  Please allow us to hide all of the sidebar extensions in vertical tabs mode.

[Jon]

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[lionelw]

Yes please, it takes up valuable vertical tab space.

Perhaps also provide an option to display sidebar extensions in an icons-only grid layout, much like pinned tabs.