When you edit a module and upload a new photo, will that replace the existing panel photo, or add an additional one? There are a few I think I could upload, but I didn't want to replace anything that's currently out there.

When you upload a new photo it will replace the old one, but the old one still is not lost.
For every upload a new version is added.
Other people who have set their module image to HEAD version (default) will see your newly uploaded image.
HEAD means: always show the newest image.
If they switch to an older version it will stick there, newly uploaded images will not affect their racks.

On a related note, why are there so many alternate panel photos that are exactly the same image?

When you click on those arrow buttons technically you browse through the versions.
The Panel Selector function was added to ModularGrid lately and is more a hack to make different images possible. It's a compromise.

-- js213

Knut

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