Geany

Geany is a powerful and lightweight programmer's text editor.

Open HTML File in Firefox

Menu Build → Set Build Commands → Execute Commands:

Execute: firefox %d/%f

Configure Build Menu - Geany Wiki

Custom Commands (Linux)

Menu Edit → Format → Send Selection to → Set Custom Commands

Command: sort
Label: Sort lines

Command: tr [:upper:] [:lower:]
Label: To lower case

Command: tr [:lower:] [:upper:]
Label: To upper case

More Info

Manual

Keybindings

Plugins

Wiki