[Bug]: Thumbnails still broken

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Summary

I can't count the number of revisions the thumbnail generation code already went through by now, but somehow it is still broken in 0.19.4-beta.4.

What happens is that posts get their thumbnail url set to the link url, even if that link is not an image. This results in most posts showing up with broken images, since the browser expects an image url.

I think the offending line is here:

lemmy/crates/api_common/src/request.rs

Line 108 in 0eaf8d3

match post.url.or(metadata.opengraph_data.image) {

The problem with that line is that it doesnt check if the post.url is an image. It should check the is_image_post boolean to verify if post.url qualifies to be used.

Version

BE 0.19.4-beta.4