[QScintilla] Support for right to left languages

[Manuel Gómez]

Hi,

Recently I changed the text editor used for displaying and editing text 
in DB cells in DB Browser for SQLite from QTextEdit to QScintilla, since 
this was already used for XML and JSON stored in cells. After the change 
a user has complained that Arabic text is not shown [1]. What it is 
strange is that the JSON lexer does display it, although left aligned. 
The text mode is using no lexer. The XML lexer has the same problem as 
no lexer: the text is not shown.

Is there a way to at least displayed the text like the JSON lexer does?

We also have an issue about incorrect rendering of mixed RTL and LTR 
characters in the SQL lexer [2].

I've updated to v2.11.1 with no visible change. However, I've seen that 
support for RTL languages in Scintilla [3] have been fixed in 2017-10-29 
(no version identified) and improved in version 4.1.0. Is this version 
planned to be used in QScintilla?

Best regards,
Manuel

[1] 
https://github.com/sqlitebrowser/sqlitebrowser/issues/1793#issuecomment-476003858
[2] https://github.com/sqlitebrowser/sqlitebrowser/issues/884
[3] https://sourceforge.net/p/scintilla/bugs/1590/