Add Expires Headers

[casper434]

I noticed recommendations from yslow on "add expires headers" but they refer to sites that plug into mine (such as a you tube video). Can anything be done about this recommendation?

[ThompsonPaul]

Nope

Neither YSlow nor PageSpeed are able to differentiate third-party content from your own hosted content in their reports. So they're giving optimisation recommendations you can't possibly implement because you don't control those external servers/code. Just ignore recommendation on any URLs you don't control.

The one exception to this is when the report mentions external JavaScript that could be moved to footers, or could be asynchronous. In those cases, do try to follow the recommendations where possible.

Remember, these are automated reports based on a standard set of rules. You must interpret them using common sense for your own specific site and circumstances - they're not gospel.

Paul