WebKit Feature Flags - Safari

For Safari settings, scroll down to the bottom of the feature flags list and select the default.

Settings > Apps > Safari > Advanced > Feature Flags > [scroll down to the bottom] Reset All to Defaults

Safari uses these flags to test new features (web browsers are immensely complex and ever-evolving apps), and to also provide an extension or continuance for when some features are deprecated and removed.

These feature flags are not intended for typical access and use.

Safari feature flags, telemetry, analytics, and related areas are intended for developers and Apple for troubleshooting snd debugging issues.

Changing Developer settings in Safari on macOS | Apple Developer Documentation

Another term for these “hacks” are “quirks”. This area uses another common definition of the word “hack”, meaning an expedient or temporary or inelegant or fragile change to the design or code involved, and not a reference to any security issues or security exploits. And sometimes ugly hacks can allow exploits, a d other ugly hacks can block exploits. Quirks as a term — for things that are expedient or temporary, or inelegant or fragile — is less problematic.

What issues might arise with Safari can have various causes, not the least of which can be websites with non-standard uses and extensions and intended and tested for specific or even one web browser. That web browser dependency used to be websites designed for Microsoft Internet Explorer, but in recent years tends to be websites designed for Chrome.

There are tools for verifying websites’ compliance with web standards too, such as the W3C validator tool.

If you have particular issues or concerns or questions about Safari, please post those.

I don't use any. I don't have any unusual problems in Safari.

What specific problems are you experiencing?