If you're using the Itch.io sandbox (which is totally fine, leave it on if you wish) I know a lot of web based applications will not work inside of it. You're best chance is to open it via browser.
If you feel like you have to have it in incognito, just copy the files location address i.e. E:\itch-games\finding-a-place (can be different) and paste it into the incognito address bar like you would a website. *quick fix: you will need to include the file + it's extension, sorry for the confusion! For me it appears as:
file:///E:/itch-games/finding-a-place/Finding%20A%20Place.html in Edge!
If not, just click on the gear icon next to the launch button, click manage, then open folder in explorer. You should find your .html file sitting right there. Double click on it and it should just automatically open in your default preference for opening html files!
Hope this helps! ^-^