Had almost the same issue. I see a background and a name with the upgrades instead of black, but no plant and tapping does nothing.
Got a couple errors in the log:
Access to fetch at 'https://static.itch.io/game.css?1672690517' from origin 'https://falkreon.itch.io' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.
And a second one for /redactor.css
Along with a couple errors that cascaded from being unable to fetch those resources.
Finally, not sure if these are linked to the first error, but:
Uncaught TypeError: Cannot use 'in' operator to search for 'unlocks' in undefined
at load (index.html:423:22)
at tick (index.html:454:5)
at frame (index.html:478:6)
adventure.js:152 Uncaught TypeError: Cannot read properties of undefined (reading 'attack_cooldown')
at attack (adventure.js:152:18)
at HTMLCanvasElement.onclick (index.html:225:155)
adventure.js:229 Uncaught TypeError: Cannot read properties of undefined (reading 'upgrade_levels')
at upgrade_adventure (adventure.js:229:21)
at HTMLDivElement.onclick (index.html:1:1)
adventure.js:152 Uncaught TypeError: Cannot read properties of undefined (reading 'attack_cooldown')
at attack (adventure.js:152:18)
at HTMLCanvasElement.onclick (index.html:225:155)