Mogan STEM Suite v1.2.1

Mogan STEM Suite v1.2.1:

Known Issues

It will crash easily when activating the structural search/replacing window
- Solution: use v1.2.2 or later version
It will crash easily when switching to Edit->Preference->General->Buffer Management->Documents in separate windows
- Solution: use v1.2.2 or later version

Fixed failure of File->Export->LaTeX introduced in v1.2.0
Fixed crash when clicking Edit->Keyboard->Keyboard Editor introduced in v1.2.0
Packaging: Create desktop shortcut and start menu shortcut on Windows
Packaging: fixed the missing .desktop file on Linux
Packaging: Support UOS (arm64 and loongarch64)
Performance: Improved font finding for truetype fonts to speedup startup for new users
UI: Add Chinese translation for all the menu entries (not including submenu), and improved several Chinese translation
UI: File-Open defaults to the user's home
UI: close an maximized Mogan and then launch Mogan, the window is still maximized without any shift on Windows
UI: switched to file explorer implemented in Qt to avoid the failure to open files occasionally
UI: add 宋体/黑体/仿宋/楷体 to the short font menu for Chinese document
Style: invalidate the style cache when a style is changed
Editing: Switch to the kde shortcut style for Deepin desktop and KDE desktop on Linux
Versioning: Fixed several bugs on Git versioning
Stability：Fixed several severe bugs which will freeze or crash Mogan