Log Message:
texstudio: update to 2.12.22

2020-01-18: 2.12.22
It fixes garbled symbols in OSX, crash when changing magic language
comment and pdf search path handling.

2020-01-13: 2.12.20
It fixes a problem with replacing when search highlight is activated.

2019-12-26: 2.12.18
This is mainly a bug fix release. Most notably change is better support
of regexp in search (Qt5 version only).