Qt 5.9 on Win7
Scintilla tip
The document's text gets drawn over the margin if SCI_SETVIEWEOL(true) is called and an EOL is being displayed.
This is using all default settings for the Scintilla instance, other than showing the eols. On the first screenshot everything is fine.

However after a new line is insterted into the document which now has an EOL to draw, the text gets drawn over top the margin.

Appears to be a clipping issue. Perhaps the line end display changes the clipping area.
Does this seem to be specific to Qt?
Yes, haven't seen it on other platforms.
Fixed by changed clipping in [f94c47] for [#2373].
Related
Bugs:
#2373Commit: [f94c47]