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Community of the Android app Boost for Lemmy

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I used to get 400 errors when posting pictures. I eventually tracked it down to image size. If I shrank it to under 500Kb it went through every time. Sometimes a little larger would go through but every picture under that made it.
That might be it. I tried clearing the app cache, and it still wouldn't go through. I can obviously make posts. The image was the problem.
I only ever had an issue when I was trying to upload an image. Text only posts were just fine.
Some instances have a pretty low limit for picture sizes.
I've had similar problems and this was the issue. The problem is there's no way to know what the requirements are from a user's point of view at the moment of posting, and the error doesn't provide useful information, so it just looks broken.
I don't know how much can be done within the app about the error messaging, but having a way to squish down the image in size and compression within the posting flow would be really helpful.