xfce – Chrome switching keyboard layouts on debian / xfce4, how to stop it?

My system runs Debian 13 and Xfce4.

Some key I hit switches the keyboard layout or input method of Google Chrome, such that the delete key is no longer the delete key.

According to my system settings, I have exactly one language installed, ‘us’. My keyboard is set to ‘system defaults’ — in fact, if I turn off system defaults, it offers me no alternatives in the dropdown.

While my fingers wander just as badly wherever I type, I have never experienced this in any other application than Chrome.