These are general questions and answers that apply to all editors.
How to change the default key binding for actions.
The default key bindings are specified in the plugin.xml file in the plugin
directory.
How to change the font color and font style in syntax highlighting.
The font colors are specified in the eclipse.editors plugin theme.xml
file. The font style is currently hard coded, you have to go into the source code to change it.
Check the xxxEditorConfiguration class and the scanner classes where tokens are created.
Why the warings and errors markers disappeared.
All warning and error markers generate by the actions is of type specific to the
EditorsPlugin. They are not persistent. They are also clear before each action.
What does the warning that about non-whitespace differences in the formatted text means.
All editors now check for non-whitespace differences between formatted text and the original
after format actions (unless disabled by user preference). Such differences may or may not be errors. Some
editor's formatter are smart enough to correct some format problems (eg. the HTMLEditor would add some
missing tags automatically). So there are occasions that such modifications are OK. However, there are also
cases that the formatter has bugs and modified the text unexpectedly. So when there are such warnings,
check it against original text (which can be restored by undo).
Note that only the first non-whitespace difference is reported. If there is a legal correction,
followed by an illegal one, it may not get noticed.