Install the plugin using the Plugin Manager and the download URL above, which points to latest version of the plugin. Refer to Plugins on how to install plugins manually.

Use this plugin to add characters to the Special Chars picker or to delete unused characters from the picker.

Enter the characters in the configuration manager, in the plugin's add or delete box, as a comma delimited list. For instance: Ж,ж,♭,♞.

Additions are appended to the end of the Special Chars character list. You can enter both additions and deletions. The deletions will be processed first; then the additions will be appended.

See gituhub repository

Currently this plugin is convenient primarily for relatively small numbers of insertions and deletions. It's possible that it could be expanded to handle larger blocks of insertions and deletions. If this might be something you need, make a note of it in the Discussion section of this page.