I updated to Discourse version v2026.8.0-latest a few days ago. Some user’s avatars have turned to a default image (not the letter avatar). Trying to upload a new image does nothing. The preview shows the image but upon saving it reverts back to the default image. It doesn’t matter if the user does …

[image] david: Looks like it’s the d-topic-previews-sidecar plugin. I’ll take a look and send them a PR for the core change. Ah, looks like this plugin is archived and no longer supported ( readme ). You should remove it from your app.yml and run ./launcher rebuild app.

Please can you share the full backtrace for that log? You can find that by visiting /logs, selecting it, and then choosing the ‘backtrace’ tab at the bottom.

Of course, here it is. Message (5 copies reported) Failed to optimize image: unknown reason Backtrace /var/www/discourse/lib/discourse.rb:1115:in 'block in Discourse.warn' /var/www/discourse/lib/discourse.rb:1109:in 'Array#each' /var/www/discourse/lib/discourse.rb:1109:in 'Discourse.warn' /var/w…

[image] Takiro: /var/www/discourse/plugins/discourse-topic-previews-sidecar/lib/topic_previews/optimized_image_extension.rb:25:in 'TopicPreviews::OptimizedImageExtension#optimize' Looks like it’s the d-topic-previews-sidecar plugin. I’ll take a look and send them a PR for the core change. …

Yes I replaced the original plugin with the legacy package after the original repo was completely removed and not accessible anymore. i try to remove it and see if that makes a difference. Here is the error message that pops up, when I try to upload an avatar here [image] But it works now, must …

[image] Takiro: At least here I get an error message about that “something went wrong I got this error after opening a topic half an hour ago. I don’t have repro steps. [Screenshot_20260730_145426_Chrome]

I removed the plugin and everything seems to be working fine again. Thanks for the help and sorry for bothering.

"Failed to optimize image" error from discourse-topic-previews-sidecar

Support

david (David Taylor) July 30, 2026, 1:01pm 8

Ah, looks like this plugin is archived and no longer supported (readme). You should remove it from your app.yml and run ./launcher rebuild app.

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"Failed to optimize image" error from discourse-topic-previews-sidecar

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