Spacing problems with paragraph

Hi I’m french so sorry if my english it’s not clear sometimes.

Since few articles now I have some problems with the spacing i between some paragraph and I don’t know why. Because some space are respected and some other not.
When I write my article the spacing is perfect and when I visualized or publish some space miss.
You can check on my last article the spacing at the beginning is just a joke.

I prefer to tell you I don’t know anything about code.

Thanks for your help

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