Backslashes disappear

I have a problem with backslashes. Every time, when a article is saved, the backslashes vanish. As a workaround I use two backslashes instead of one. The first one disappear but the second is still there. When I save the article a second time, the remaining backslash also disappear. So I have to add an extra backslash every time before saving. 🙁

Is there a way to solve this problem?

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