I use an app I made called ghostnote which basically allow you add attach notes in context of what you are doing currently working on. But I like your idea of using messenger or something like that as a, even more, laissez-faire approach
The whole point is to write the idea down, not so much remembering it (unless you literally have the melody for a hit song or the algorithm for the cure for cancer)
The whole point is to write the idea down, not so much remembering it (unless you literally have the melody for a hit song or the algorithm for the cure for cancer)