I took BareBones at their word when they said "We have identified several bugs and regressions in macOS 14 which affect BBEdit's performance and stability. (FB13219490, FB13213147, FB13264033) For that reason we recommend that you remain on an older compatible version of macOS until such time as Apple addresses these issues. As and when that happens, we will amend our advice accordingly." on their Mac OS Sonoma Compatibility page (
https://www.barebones.com/support/bbedit/macos-14.html). Aside from that warning I don't know what the specific problems were.