Soundless is a simple and choiceless visual novel, so for the most part visual indicators are limited to button colors changing when they're selected. These buttons are set up with alternate text that tells you if the button has been selected or not.
The sole visual indicator that lacks alternative text is the click-to-continue indicator. Fully blind players have to rely on an obvious lack of text being read aloud to figure out that it's okay to advance.
The upcoming ability to have auto-forward mode and text-to-speech mode on at the same time will remove the indicator because of the auto-advancement. However, we would like to ask you if it would be even more helpful for there to be alternative text for the click-to-continue indicator regardless, especially since some people prefer to have full control over their text advancement speed. We can bring it up on the Ren'Py GitHub page and workshop a way to implement it with other developers.