Does it keep paragraphs?

No — all breaks are removed; disable 'collapse blank lines' to keep double breaks as single.

Are extra spaces cleaned?

Yes, runs of spaces are collapsed to one.

Strip line breaks to join text into one block.

Replace breaks withCollapse blank lines first

Input

Output

First line Second line Third line

Remove newlines from text, optionally collapsing blank lines and replacing breaks with a space.

Does it keep paragraphs?: No — all breaks are removed; disable 'collapse blank lines' to keep double breaks as single.
Are extra spaces cleaned?: Yes, runs of spaces are collapsed to one.