https://caniuse.com is useful because it is a large(ish) database of web platform features (186 at the moment) and their precise availability. The fact that a) caniphp does not contain any stats about proliferation of PHP versions, and b) the existing PHP documentation (example: Fibers) already has information about which PHP versions support the feature, makes me doubt this will be used by many developers.
If you use PHPStorm or other IntelliJ IDEs, you can set the version of PHP you target for your project already, and it will tell you which features are not available by marking them red in your code. No switch to the browser necessary.
https://caniuse.com is useful because it is a large(ish) database of web platform features (186 at the moment) and their precise availability. The fact that a) caniphp does not contain any stats about proliferation of PHP versions, and b) the existing PHP documentation (example: Fibers) already has information about which PHP versions support the feature, makes me doubt this will be used by many developers.
If you use PHPStorm or other IntelliJ IDEs, you can set the version of PHP you target for your project already, and it will tell you which features are not available by marking them red in your code. No switch to the browser necessary.