Gedit – Can Gedit Default Highlighting Style Be Set for Files Without an Extension?


I frequently work with text files that do not have an extension or which have a non-standard extension using Gedit (a .sample file for example, for which the mime type is not understood), and Gedit always defaults to Matlab syntax highlighting.

gedit highlight settings

I'd like to set a default syntax highlighting of 'Plain Text' for these files. Is this possible?

Nano can do this, and a similar question for files with extensions is here. I'm looking for an answer that allows me to set a catch-all style of plain text for all types without an extension or not already found in /usr/share/gtksourceview-3.0/language-specs/as described here

Requested info:

  • No local language spec file in ~/.local/share/gtksourceview-3.0/language-specs/
  • Output of file --mime-type -b <myfile> is correct text/plain

Best Answer

Steps taken

In my gedit, from the top bar menu, I select View, Highlight mode... and "Plain Text" is the default as shown below:

gedit highlight mode

Using the file name "test.sample" and pasting in a few lines of Matlab code it still stays as "Plain Text" format unless I force it to "Matlab" format.

After saving and exiting I performed cp test.sample test.newbee followed by gedit test.newbee the default format is still "Plain Text".

Next I created a new file using gedit called noextention. I typed a sentence, saved the new file and exited. Then I reopened the file using gedit and this is the result:

enter image description here

Notice the bottom bar of gedit's window shows Plain Text option for highlighting.


This was done under Ubuntu 16.04, Kernel 4.4.0-53.

I can confirm that <property name="globs">*.m</property> exists within /usr/share/gtksourceview-3.0/language-specs/matlab.lang.

Because I can't break my system like yours, unless we find something on your system to fix, I suggest reinstalling gedit after removing and purging all it's files with apt-get.

Particulars about my version:

$ sudo apt install gedit
Reading package lists... Done
Building dependency tree       
Reading state information... Done
gedit is already the newest version (3.18.3-0ubuntu4).
0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.