Arrange object after unhide
Using Adobe InDesign 15.0.1 x64 (CC 2020), after I unhid several linked image objects, I was unable to arrange those elements forward or backward to make it visible on top of other elements. The objects were not locked as I checked several times and even copying / pasting them would not allow me to rearrange them. Restarting solved the problem after I spent 20 minutes fighting with it.
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Joseph commented
Using Adobe InDesign 15.0.1 x64 (CC 2020), after I unhid several linked image objects, I was unable to arrange those elements forward or backward to make it visible on top of other elements. The objects were not locked as I checked several times and even copying / pasting them would not allow me to rearrange them. Restarting solved the problem after I spent 20 minutes fighting with it.