Undo always display images
How do I undo “always display images from this sender” on Android gmail? - Android Enthusiasts Stack Exchange Accidentally clicked twice on the “Display images” using Android Gmail. This causes images to always show from that sender. If you don’t want that for some reason (tracking pixels etc), go to settings / general settings and click the three dots settings icon. You should see an option to Clear picture approvals. Click on that and confirm it.
Be warned, this will clear the picture approval for ALL senders.