I've tested a few apps that have either an "agree to terms and conditions" checkbox or a "don't show again" checkbox, and I can't check the checkbox with my keyboard. All other buttons I can press by using the enter key, but not this one. Is there a way to turn the functionality on? Here's an example of one with the button https://experience.arcgis.com/experience/f85c4563dab548e0bbd400df1a411e76
Use the tab key until there is a blue outline over the checkbox. Click enter once there is the blue outline and try to click enter.