Private Desktop Apps by You for You ONLY
Almost anyone can learn to build a simple app to encrypt their own passphrase mnemonics.
You need not worry about forgetting your own passphrases or exposing them on your personal device.
I use free MIT Curl from SCSK for making Windows, Apple or Linux app’s.
You might prefer Pharo Smalltalk, Python or Ruby, but soon there will a very pythonic version of Icon called Converge and there soon will be a new version of rebol called Red.
Anyone can learn to program in a language such as Icon. It was created to be free and for non-programmers working with text. Unicon.org has a Unicode variant suitable for passphrases. Form a group and learn it if you are retired!
There is also a new language in the works at UMN but I say no more.
The author of Converge is a great guy and very bright: Laurie Tratt in UK.
Unicon is now based in Moscow IDAHO at that state U ( Icon began at the new Tucson dept of CS when it was begun by Ralph Griswold who also gave the world free SNOBOL back at Bell Labs.)
Red in being developed by Peking but comes out of western Europe. Not to worry: China gives us lots of great stuff. It is completely transparent code on a GIT hub.