[Bug]: Custom selector silently drops duplicate content images

[Akul-Tyagi]

Summary

In the custom selector flow, if a user selects multiple files where some are duplicate-content images (the same image content or hash), the app silently drops the duplicates and returns fewer images than the user selected. This creates a mismatch between the selected count and the upload count, leading users to believe the selection process is broken. This behavior also creates an inconsistency, as it does not match the normal selector which keeps all selected images.

Steps to reproduce

1. Open the app and initiate an upload using the Custom Selector.
2. Select 5 images, ensuring at least 2 are exact duplicate - content copies (to test - download a image twice from somewhere if not having duplicate images already).
3. Tap Upload.
4. Observe the number of images passed to the upload details screen.

Expected behaviour

The custom selector should keep all images the user selected without silently reducing the count. If duplicates are detected, it should show a clear warning popup (with options to proceed or review the selection) so the user at least understands what happened.

Actual behaviour

Only unique content images are kept (e.g., 5 selected in which 2 images are duplicate-> only 4 passed) with no warning or explanation provided to the user.

Device name

Samsung M34

Android version

Android 16

Commons app version

6.3.0

Device logs

No response

Screenshots

Screen_Recording_20260318_082650_Commons.mp4

Would you like to work on the issue?

Yes

[Akul-Tyagi]

Hi again! As discussed in PR #6752 , I have investigated this and put together a minimal fix. I updated the custom selector to preserve the selection count and added a Material warning dialog that gives the user the option to either proceed or review their selection. I will open a PR with the code shortly!