This happens to me occasionally as well, and it is very annoying. If you go to jira.atlassain.com and search for "cell borders" you'll find quite a few tickets where people are complaining about borders disappearing or not rendering properly in several different situations. Unfortunately none of these tickets have a high priority, and so are unlikely to be fixed. That doesn't help you, but be assured you're not the only person with this problem.
You might want to check out some of the table add-ons here. Some are paid, some are free, and they should help you get a better table experience.
Hi my Community friends! For those who don't know me, I'm a product marketer on the Confluence Cloud team - nice to meet you! For those of you who do, you know that I've been all up in your Co...
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