Previously we would render these with their code point value but since there are probably a few hundred glyphs available (on OS X) in the private use area, it was a disputed choice.
We now explicitly disable it for targets that hasn’t yet been upgraded to ARC. This way, it’s easier to get an overview of which targets hasn’t yet been upgraded and ensures new targets has ARC enabled.
When we wish to (ab)use the indented fold system to fold sections in markup languages we set the ignore pattern to ignore all but the heading markers. Some markup languages also have markup that might be suitable for folding with explicit start/stop markers, previously these were ignored, if matched by the ignore pattern.
This is an incomplete fix as we don’t correctly nest a start/stop marked block inside a section (the section will stop at the fold start marker).
There is a bunch of functions that deal with the logical column count and these now all count code points with the “east asian width” (unicode) property set as two columns.
This closes issue #206.