Tuesday December 19, 2023

Issue summary:
From 1:43 PM PST on December 19, 2023 to 10:25 AM PST on December 20, 2023, a small number of users experienced seeing blurred file previews. We discovered that this affected users with international data residency enabled in their workspace.

A change was made to our file storage, resulting in unexpected behaviour with file previews. We promptly identified the problematic code and reverted back the change in an effort to prevent file previews from becoming blurred.
We later ran a script to fix affected files to display with clear previews, resolving the issue for all affected users.

6:01 PM PST

We've resolved the issue with blurred file previews in Slack. Previously uploaded files should no longer display a blurred preview.

It's recommended for anyone still seeing the issue to hard refresh their Slack app by pressing Cmd/Ctrl + Shift + R.

We apologize for the trouble this may have caused and appreciate your patience while we sorted things out.

10:51 AM PST

We're continuing to work towards a fix and will provide an update when this is completely resolved.

In the meantime and as a workaround, if the image remains blurry, please expand the image and Slack will load the full size version.

7:37 PM PST

We have identified the cause of images being blurry in Slack and customers can now upload and preview new images without issue.

We are still continuing to work on regenerating the previews of older affected images.

We will provide an update when functionality is fully restored. Thank you for bearing with us in the meantime.

6:47 PM PST

Customers have reported seeing blurred images within Slack until clicking the preview option. It's also been reported that PDF files are not downloading as the correct file type.

Our engineers are in the testing stage and are reverting some items in the back-end, which has lead to them seeing small improvements with file unfurl behaviour.

We will provide further updates once our engineers have a resolution in progress. We're sorry for the disruption.

5:37 PM PST

Customers have reported seeing blurred images within Slack until clicking the preview option. It's also been reported that PDF files are not downloading as the correct file type.

Our engineers are in the process of investigating the root cause and are working hard to resolve this for users.

We will provide further updates once our engineers have a resolution in progress. We're sorry for the disruption.

5:05 PM PST

Further to reports about blurred images in Slack, we're also receiving reports on issues with downloading and viewing PDF files.

We're currently reviewing the scope of impact to see what customers could be affected. We will provide further updates once we have more details to share. We're sorry for the disruption.

4:26 PM PST

We're receiving reports about blurred images in Slack. The image does display as expected after clicking the image preview.

We're on the case and will provide another update once we have more details to share. We're sorry for the disruption.

3:56 PM PST