This happens when you use "preview post," and I've encountered the problem on other fora before. I figured it was something to do with not being able to turn scripts off in my potato-mode browser, most likely with how the various buttons and things on the editor are implemented since all that also goes away with scripts turned off. Going to the mode that lets you see and edit tags as plain text may also mitigate the problem, IIRC.
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‎noli esse culus
‎noli esse culus