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It would be good if #2073 could be extended to show CRLF / LF indicators if the file has mixed line endings. (Ew!)

It could look like how bat shows non-printable characters:

(Compare line 10 and line 11. Ignore the rest of the screenshot, this feature proposal is just about line endings. Not other non-printable characters.)

Why?

The current show-whitespaces feature has been fantastic in stopping tabs appears where they shouldn't (.editorconfig helps, but not everyone uses an IDE that supports it).

This feature will stop pesky CRLFs appearing where we don't want them.