Subresource Integrity (SRI) is a new W3C specification that allows web developers to ensure that resources hosted on third-party servers have not been tampered with. Websites that make use of SRI can break when CSS patching is used within APM Portal Access. This very basic snippet will simply disable SRI by removing it.
The picture below shows an example of Chrome blocking a stylesheet from being loading (Chrome DevTools -> Console).
Assign both a STREAM profile and this iRule to the Virtual Server.
Just as a side note: the stream profile is under advanced settings of the virtual server.