I've been a long-time in-browser slack user and yesterday Firefox refused to open any slack link, bookmark, or history entry I had. Closing all my tabs and relaunching FF did not help either.
In a pinch I installed the desktop app, and once I had a little bit of spare time I googled around and figured out the issue. Which was that Slack had used 2GB of Cookies/Site Data and Firefox neglected to notify me of that and that appears to be a hard limit and prevent Slack from loading. Clearing the data resolved the issue.
In a pinch I installed the desktop app, and once I had a little bit of spare time I googled around and figured out the issue. Which was that Slack had used 2GB of Cookies/Site Data and Firefox neglected to notify me of that and that appears to be a hard limit and prevent Slack from loading. Clearing the data resolved the issue.