Is there any reason why my thumbnails for cards keep being replaced with grey caution signs?

[Smirky]

Hello all, wanted to ask and see how to potentially fix a bug I'm having with trello at the moment. We use trello boards as a helpful informational tool for our game but this bug is hindering our work. Our gifs and images are being replaced with this big grey caution sign, sometimes when we upload something new it will fix itself but then 10 minutes later its broken again. Any help is appreciated.

[Arkadiusz Wroblewski]

Hello @Smirky 

A grey caution icon usually means Trello's thumbnail generator failed or a network blocker is stopping the image from loading.

First, ensure the file is uploaded directly to the card rather than linked externally, and test a standard JPG instead of a GIF in an incognito window. If the issue happens for multiple users across different networks, it's likely a backend glitch rather than a local firewall or ad-blocker problem, and you should reach out to Trello Support with a few affected card links.

Best,

Arkadiusz🤠