Strange behavior indeed.. you should check this page; https://confluence.atlassian.com/confkb/editor-does-not-work-properly-315326472.html
It could be due to;
There are quite some good ways to hopefully resolve your problem on there.
Over the next several weeks we'll be sharing some of our Getting Started guides here in the community. Throughout this series of posts, we'd love to hear from customers and non-customers ab...
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