@guy038 said:
Now if, for any font, you select all the text of that new tab and run an Edit > Line Operations > Split Lines operation, for most of them, indeed, the spliting behaviour occured right after the 78 capital letter P.
However, for eample :
For the proportional Times New Roman font, the spliting action occured after 76 letters P
For the fixed witdh **``Consolas font, the spliting action occured after 77 letters P
The explanation may lie in something I discovered while bug-hunting in the Elastic tabstops function of Columns++: when DirectWrite is in use, the width of characters can work out to fractional pixels (this is true for both fixed and proportional fonts); but Scintilla only reports the width of strings as integers. So due to the effect of rounding to integers, the width of a string of 78 letters P is not necessarily 78 times the (reported) width of one letter P. Notepad++ uses 78 times the width of one letter P. (Not that it matters much, since none of this is likely to be what anyone wants or expects anyway.)