i found in thunar there r cutom actions for making item in contextmenu, like open as root for folder, and i found edit as root for text files, but it doesn't worked with me:
### Edit file as root
* Name: **Edit as root**
* Command: `gksu put-your-favourite-text-editor-here %f`
* File pattern: *
* Appears if selection contains: Text files
**Note:** You'll need to replace put-your-favourite-text-editor-here with your favourite text editor (e.g. mousepad or geany). Also, see previous note about `gksu`.
but that not worked , just pop up message and when type password, no text open
Currently you have three topics open on this issue. @jgordon last posted a usable workaround here;
The app gksu was deprecated due to a security vulnerability that the developers could not readily fix.
The app pkexec somewhat replaces it, but not fully. Pkexec does not work with all applications.
It should work on thunar: