I found this conversation when digging deeper.
Summary: You need to add some code to your manifest file appscript.json:
"webapp": { "access": "MYSELF", "executeAs": "USER_DEPLOYING" },
The whole appscript.json file should look like this (so you can see where to place the code:
{ "timeZone": "America/New_York", "dependencies": { }, "webapp": { "access": "MYSELF", "executeAs": "USER_DEPLOYING" }, "exceptionLogging": "STACKDRIVER" }
Furthermore here is an overview of the different options available (full documentation here https://developers.google.com/apps-script/manifest/web-app-api-executable?hl=fr#webapp):
"webapp": { "access": "MYSELF" "access": "DOMAIN" "access": "ANYONE" "access": "ANYONEANYONE_ANONYMOUS", "executeAs": "USER_DEPLOYING" "executeAs": "USER_ACCESSING" "executeAs": "ANYONE_ANONYMOUS" },
After updating the manifest file push the changes using clasp push. Then deploy with the commands in the instructions: clasp deploy --deploymentId abcd1234
Additional note to anyone new to clasp: there is a difference between version and deployment. A version is similar to a git tag (a way of keeping track of code), while a deployment is actual code that is being used for execution.