Change case
This plugin helps you to change the case of selected portions of text. You can use it to change text to be all lower case, all upper case, to invert the case, or apply title case. To enable this plugin, select gedit ▸ Preferences ▸ Plugins ▸ Change Case.
Once the Change Case plugin is enabled, you can use it by completing the following steps:
Highlight the portion of text that you want to change.
Select gedit ▸ Change Case
Choose your desired text-formatting option.
The updates to the text formatting will take place immediately.
The Invert Case option will convert all lower case letters to upper case, and will convert all upper case letters to lower case.
The Title Case option will convert the first letter of each word to upper case. All other letters will be converted to lower case.
If you have not highlighted any text, the Change Case feature will be grayed-out. You need to select a portion of text before you use the Change Case feature.