Afterward, restart the app in question.

Turn off bounce#

Globally#

$ defaults write -g NSScrollViewRubberbanding -int 0

App Specific#

$ defaults write com.apple.mail NSScrollViewRubberbanding -int 0

Restore bounce#

Globally#

$ defaults delete -g NSScrollViewRubberbanding

App Specific#

$ defaults delete com.apple.mail NSScrollViewRubberbanding

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Mac