I am running Lightroom Classic 12.0.1 on a Windows 11 PC. I have a problem with "Select Subject" not working on a specific group of bird photos. On other bird photos it works fine. This has never happened to me before. Normally, the frame around the "Select Subject" panel lights up and then you click to select the subject. When I hover over the "Select Subject" panel it doesn't even light up. Clicking on the panel does nothing. Here's two examples, one that worked and one that didn't.
Whenever LrC shows erratic behavior, the first thing to reset the preferences. Also restart the computer.
In your second screenshot, in the histogram panel, note the lighting bolt symbol bottom right corner (of the panel) .
Your selected photo is using an older process. Maybe imported long long ago? As a result, newer edit tools do not function, surprised they show up at all.
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