The other day I found a great post that explained how to add a custom button to the WordPress Visual TinyMCE editor.1 It was fairly simple and concise and even includes a zip file of all the parts you would need to install a button into WordPress’s visual TinyMCE editor. I’m not at all sure I could do a better job than that guy, so I’ll just direct you to the link above. :)
Default Series Title- Photo courtesy of Marco Bernardini [↩]
I can recommend Shotcut. https://www.shotcut.org/
Open the files, drop them into a video, export.
;)