Official webkit no longer supports Mac 10.14. However, we still want to download a latest good version of
WebKit for Mac 10.14 that supports all the good Playwright features.

Things to do:

• fork our webkit fork - with the last known WebKit version that compiles on Mac 10.14
• download a compatible webkit version on Mac 10.14
• setup bots on Mac 10.14 to make sure things work