every time use Command + S to format the code , the bold style disappear , becomes normal ...

[leewi9]

not sure it's Xcode issue or BBUncrustifyPlugin-Xcode issue, pls see this gif for detail:

[benoitsan]

I really think it's not related to the plugin. There are some strange bugs from Xcode when using bold/italic fonts in Xcode. For example, in this screencast http://cl.ly/fX6B, you see that the italic font is not always applied, you need to switch to another file to see the italic font applied.

Now I think you see this a lot with the plugin because all these bugs are amplified since it reformats the code so Xcode needs to reapply the theme to the textview.