1) Open devtools. 2) Select the "Accessibility" panel. See https://developer.mozilla.org/en-US/docs/Tools/Accessibility_inspector#Accessing_the_Accessibility_

1) Open devtools. 2) Select the "Accessibility" panel. See https://developer.mozilla.org/en-US/docs/Tools/Accessibility_inspector#Accessing_the_Accessibility_Inspector https://developer.mozilla.org/en-US/docs/Tools/Accessibility... 3) In Firefox 70 or newer, if WebRender is enabled, there will be a "Simulate" menu next to the "Check for Issues" menu. See https://developer.mozilla.org/en-US/docs/Tools/Accessibility_inspector/Simulation https://developer.mozilla.org/en-US/docs/Tools/Accessibility... for details. Note that WebRender is not enabled across the board yet, so you may need to force-enable it, depending on your operating system and graphics card, to use this tool.