HTTP status code 500 indicates an internal server error. Something is wrong with the instance, not with Summit.
Summit
Community to discuss Summit, a Lemmy reader for Android.
App (Play Store): https://play.google.com/store/apps/details?id=com.idunnololz.summit
APK: https://github.com/idunnololz/summit-for-lemmy/releases
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Website: https://summit.idunnololz.com/
Tried and can't even select a photo, it gets stuck like this:
Have you tried a smaller file size? Weird that it didn't even work with image links.
If it's via URL then you are not uploading anything so that shouldn't fail with an upload error. If you are seeing that error with a URL please report that because that's a bug.
That being said because this is a 500 it's hard to tell what the issue is. I have found that the Lemmy servers are picky with images and will fail for some reasons such as:
- image format is not supported (eg. trying to upload a heif image)
- image resolution not supported (either the width or height of your image is too large)
As a potential workaround you can try upload images to imgur. To enable this go to Settings > Misc > Use Imgur.