Blender Plugin to merge any amount of selected bones into the active bone, with respect to any meshes and their vertex groups.
- download the .py file (download the whole repo if you don't have a browser extension to get only that file
- in blender, Preferences > Add-ons > install
- Enabled Addon
- select the armature you wish to edit
- select the bones you want to merge, the last you select (the one with a slightly brighter color) is the active and target bone. the other bones will be merged into it.
- rick click, at the bottom "merge Bones"