Angular 11 production fails with error: ERROR TypeError: Object(...) is not a function

Question

Recently in my company there was an upgrade of angular app version to 11. App locally compiles and runs without a problem with ng serve, however it fails on ng serve --prod with following error:

main.js:1 ERROR TypeError: Object(...) is not a function
    at e.value (main.js:1:942704)
    at e.value (main.js:1:942493)
    at e.value (main.js:1:941765)
    at new e (main.js:1:1099073)
    at Pr (main.js:1:145982)
    at Mr (main.js:1:144712)
    at Uo (main.js:1:182147)
    at Lo (main.js:1:180936)
    at Object.ia [as createRootView] (main.js:1:190182)
    at n.value (main.js:1:136423)
bt @ main.js:1

TypeError: Object(...) is not a function
    at e.value (main.js:1:942704)
    at e.value (main.js:1:942493)
    at e.value (main.js:1:941765)
    at new e (main.js:1:1099073)
    at Pr (main.js:1:145982)
    at Mr (main.js:1:144712)
    at Uo (main.js:1:182147)
    at Lo (main.js:1:180936)
    at Object.ia [as createRootView] (main.js:1:190182)
    at n.value (main.js:1:136423)

I've tried removing rxjs-compat as suggested here. After doing that, production build completely fails, because rxjs-compat is apparently used, even though with Shift + Ctrl + F in Visual Studio nothing is found. I also tried adding rules to tslint.json as suggested here, but that didn't do aything as well. Any suggestions for debugging production code or fixing this issue are welcome.