Open the Activities overview and
start typing Universal Access.
Click on Universal Access to open the panel.
Press Typing Assist (AccessX) in the Typing
section.
Switch Bounce Keys to ON.
バウンスキーのオン/オフをすばやく切り替える
You can turn bounce keys on and off by clicking the
accessibility icon on the top bar and
selecting Bounce Keys. The accessibility icon is visible when
one or more settings have been enabled from the Universal Access
panel.