Problem: filtering lines through "cat", without changing the line count,
changes manual folds.
Solution: Change how marks and folds are adjusted. (Matthew Malcomson, from
neovim #6194.
Problem: When using indent folding and changing indent the wrong fold is
opened. (Jonathan Fudger)
Solution: Open the fold under the cursor a bit later. (Christian Brabandt)
Problem: An address relative to the current line, ":.,+3y", does not work
properly on a closed fold. (Efraim Yawitz)
Solution: Correct for including the closed fold. (Christian Brabandt)
