[chaot]

@Tex2002ans, thank you very much!

That looks like a lot of work - and you will probably be able and willing to help in cause of other related questions.

Originally Posted by Tex2002ans

Question: Is there an actual space before the final closing </p>? And can it actually be relied upon?

At the moment I can't answer that, subject to an investigation.

In my experience, I wouldn't trust this with a ten foot pole, and would have to check each one on a case-by-case basis. I definitely wouldn't completely rely on a Replace All.

Nothing beats experience! The examples shown concern only 3 books, other hundreds/thousands waits. And so far, even if it is very time consuming, I will consider your advice to be careful with Replace all.
Note: Adding an Example 3a in Post #1 (same book as Example 3)

Treating the whole catalog of problems at once I often lack the Internet, that means going on selective. Simple things first.

Regex Solutions

I would handle this specific cleanup in a few passes.

First, make sure that you SAVE A COPY before you do anything. Then make sure you don't press Replace All unless you know exactly what you are doing (and have tested a few to make sure the Regex is working properly). Even then, make sure you do a code comparison of the Before/After to make sure you didn't delete key parts of the text.

Code comparison, what kind of tool will do the job best? I got Beyond Compare, Meld and KDiff3.
Probably you mean key parts of the code!?

Example #5

Search: \[[0-9]+\]
Replace: *BLANK OR the regex, however, should eliminate a blank space

Note: In English, Red says "look for a left bracket" + "look for 1 or more numbers in a row" + "look for a right bracket".

Replace: *BLANK OR A SPACE* will transform

ihr Büro war für die [306] Sicherheit

into

ihr Büro war für die  Sicherheit [2 blank spaces]

respectively into

ihr Büro war für die    Sicherheit [4 blank spaces]

The regex here, however, should eliminate with [306] also a blank space.
Don't be angry, I'm relatively sure the solution (for the elimination of a space) is
to find anywhere - only I would like a little sense of achievement quick and now.

What's the different in S&R between settings Regex and Regex-Function?

I would highly recommend learning at least the basics of Regex

Will be done! Great interest exists.

There is also a huge "Regex examples" thread in the Sigil section of the forums:

https://www.mobileread.com/forums/sho...d.php?t=167971

Stupid question!? Are these regaxes also fit for calibre?
Would may be worth to create out of all these examples there something like a (regax examples) library - you know, cataloged and without bla-bla.