I have to upgrade a production php webserver from php-5.6 to 7.2. While upgrading to 7.2 I run to lot of deprecation inside 3d-party libraries. I did not developed the project. And it seems that the project does not use any package manager software (like composer).
The first deprecation error is located in nette.php (Nette) but I am afraid that there will be more deprecation errors.
What would be the best approach to tackle this task?