The icons at the bottom of the screen have ended up too large and they obscure what's underneath. I hve no idea how it happened, but can I reset LR so it uses some default workspace arrangement?
in most adobe programs you click window>workspace and select a workspace (including default ones).
Moving to Lightroom Classic CC
A known problem- Read the forum links-
Filmstrip in Lightroom CC overlaps and cannot be reduced
Filmstrip is covering / overlapping filter- and breadcrumb bar | Photoshop Family Customer Community
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