Can you attach some screenshots? I cannot reproduce it. Which build do you use?

Well, it sounds like a Strip Whitespace plugin problem. I'm not sure who the maintainers are, but hopefully somebody
will pick this up.

Created attachment 50522 [details]
Before enter hit three times

Created attachment 50523 [details]
After enter hit three times

Shot1 is before any changes.

Shot2 is just after I hit enter at the end of line 32 (//TODO code ....) three times.

The real problem is that the editor inserts useless trailing whitespace as you edit. This has long been complained about.

I see, thanks for the screenshots. I'm not sure if we want to fix this. The expected behavior is that after pressing
enter the new line is correctly indented. That's why the editor inserts spaces there. IMO Swing based editors are bound
to do that, because caret positioning is based on document offsets (not visual coordinates), so there has to be
whitespace characters present in the document.

But the editor could nonetheless remove trailing whitespace from an edited line after moving away from it (or saving).
Thus you would have

---%<--- #1
void m() {<<CARET>>
}
---%<--- ENTER => #2
void m() {
____<<CARET>>
}
---%<--- some text => #3
void m() {
____doSomething();<<CARET>>
}
---%<--- ENTER => #4
void m() {
____doSomething();
____<<CARET>>
}
---%<--- ENTER => #5
void m() {
____doSomething();

____<<CARET>>
}
---%<--- some text => #6
void m() {
____doSomething();

____doSomethingElse();<<CARET>>
}
---%<--- ENTER => #7
void m() {
____doSomething();

____doSomethingElse();
____<<CARET>>
}
---%<--- Save => #8
void m() {
____doSomething();

____doSomethingElse();
<<CARET>>
}
---%<---

which would work fine with a Swing editor yet still prevent the introduction of unwanted trailing spaces.

Yeah, I see what you mean, but I don't think it would be that easy. For example what if in #4 you don't press enter, but
simply use up/down arrow or any other means of navigation to move away from the line? Should the whitspace [a] stay or
[b] be removed.

a. If it stays then you will eventually end up with trailing whitespace in your files anyway. So, the feature does not
work properly and we will have to battle this type of defects forever.

b. Removing the whitespace means that simple navigation modifies the document, which IMO is very unexpected.

I'm really sorry, but to me this looks like too much hassle for nothing. If you guys have strong objection please reopen
the defect, but unless somebody volunteers to implement this and more importantly socialize it among people this is
going to be on the back burner anyway.

(b), though only if the line was just edited anyway. Alternately: (a) but remove it upon save. The ideal outcome is that
no line which has been edited is left with trailing whitespace. (Removing whitespace from unedited lines is potentially
rude to a VCS so this is probably best avoided, or at least made optional.)

This isn't a DEFECT - the editor is working as designed - but it is certainly not "nothing"; people have been
complaining for a long time that NB's editor adds trailing whitespaces to documents, hence the various contributed
modules to detect and remove it. Probably a new module is needed to implement the suggested behavior; I don't know if
there is some kind of pre-save hook in the NB editor, but that would be needed.

See issue #13063, with 17 votes and at least 5 duplicates.

Ok, ok, I can see that there is enough people who care about this and we should not just simply throw it into a rubbish
bin. Will everybody be fine if I mark this as duplicate of #13063?

Up to reporter I guess...

*** This issue has been marked as a duplicate of 13063 ***