Hi, for a few days now, Youtube embedded videos do not show as image preview neither in the composer nor on my home page, which uses the Topics lists plugin.

Victory ! That solution worked: After playing around for a bit, I disabled the “Block onebox on redirect” setting, which fixed the issue for youtu.be links, although I need to rebuilt HTML on old posts.

Hey there, is this happening after an upgrade, or out of the blue? Also what version are you on, and have you tried other videos? Have you tried safe mode?

Check you haven’t run out of space (download remote images threshold). If you have: clear space (./launcher cleanup app etc.) and re-enable download remote images to local (which gets auto-switched OFF)

Hi, Discourse version 3.6.0.beta1-dev safe mode, can’t tell because in safe mode topic list TC is not active so it’s normal the thumbnail does not show Issue already was here before the last upgrade

It’s not that: 14.3 Go available

So for example why my last video and all new ones don”t show a preview image as the previous ones in the same categories were ok? Tutoriels Fusion - Dessein-Tech

Most probably a TC interference because I posted the very same content on my other Discourse site (not the same TCs installed) and the issue did not happened… Will try disabling the TCs one by one :smirking_face:

Well, no, disabling the TCS does not change things… :thinking:

Some news, if I publish in safe-mode I do not have the bug ! Not very practical I must say but the only way, I, as an admin, can publish a Youtube video for now on… Unfortunately for my members… Also if I edit a topic which has generated no preview Youtube image in safe-mode, the preview reappears even in normal mode…

Youtube image preview do not show

Product Support

patrickemin (Patrick EMIN) September 15, 2025, 11:57pm 10

My issue seems very similar to that one: Youtube issues after update

Topic		Replies	Views
YouTube embeds appearing way too small Product Support	16	470	August 3, 2024
Video previews no longer show up since 3.2.0.beta3 Product Support	2	496	November 13, 2023
No YouTube preview available Product Support	5	1139	April 9, 2021
Youtube links don't show preview anymore Product Support	4	2130	November 8, 2024
Is there any way to check I chose the correct video without publishing the topic? Product Support	1	355	May 29, 2024

Youtube image preview do not show

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