All imported things gives "is not a known element" or "Can't bind to" after upgrade from v15 to v16

[ruby scarab]

Hello !

I had to migrate a project from v15 to v16. Upgrade with ng update works but when I try to run ng serve or ng build I have a lot (1286) errors. Seems all errors I checked are "is not a known element" on Components (from the project or from lib like <router-outlet><router-outlet/>) or "Can't bind to" for directives

I already tested:

• checked the other deps and upgrade them us much as possible ;
• node version (I was on v19.5 so redo the migration with node v18.20.4) ;
• no errors on app.module.ts (pretty everything is declared in that module) ;
• checked some of the component to being correctly declared/imported ;
• checked the upgrade guide twice (to ensure I did not missed a step) ;
• checked official blog post (and some others like Ninja Squad's one) to check if I missed a big change ;

Everything is working on v15 but not on v16. I cannot find similar problem solved online, maybe someone have a idea?

[red tree]

@ruby scarab try deleting .angular folder and node modules, then install deps once gaian

[ruby scarab]

I forgot to say it but I also tried this (I try again with delete of .angular, node_modules and package-lock.json to be fully sure)

exactly the same after deleting .angular / node_modules / package-lock.json