Preview doesn't necessarily tell how final, saved page will look like

[Mars icecream 57]

Not long time ago I had an odd issue with Firefox, my browser randomly added line breaks to submitted text (I have now performed a factory reset). I was aware of the problem when editing PCGW articles, but thought that 'show preview' feature is infallible. Everything was fine when previewing, but after saving line breaks were added everywhere and entire articles were broken.
I have only recently started editing, didn't know how to roll back changes.

[Mars icecream 57]

this sounds most likely to be caused by a 3rd party extension. After all, we use the same software (slightly older) as Wikipedia with thousands of editors

[Pridit 39]

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