If this was a VB app I would put : grid1.enabled = false to prevent this kind of problem when record button is disable.

This completely ignores that the pop-up is a deliberate and wanted feature; If you prefer not to see this popup and accidentally enable editing, you can set the NoEditPopup secret setting.

The only thing up for discussion here isn't the popup itself but whether the "E" key should be an mnemonic key for accepting the popup as it currently is. It is probably a bit too dangerous because it it can also be used for note and effect entry.

I figured out that the mnemonic "E" is being chosen by Windows because we did not provide a mnemonic ourselves. I think setting the mnemonic key to the space character would avoid most accidental edits in this context.

Perhaps the messageBox should not give the possibility to activate a record session so the E key will not affect this. A WarningMessage 'click on the record button if you want to activate a record' with a simple OK button could perhaps solve the problem.

As said, I could offer to change the mnemonic key from E to Space. Even if there was an OK button it could still be triggered with the space bar, so you wouldn't gain anything.

The mnemonic character has now been modified so that the popup can no longer be dismissed with one accidental keypress. If you change OpenMPT's update channel to "next", you should receive an update with the fix by tomorrow. Alterantively, build r11932 will be available from https://builds.openmpt.org/builds/ within the next few hours.