Updating the manifest mf
Browsers only update an application cache when the manifest file changes, byte for byte.
If you change a cached resource (for example, you update the image with new content), you must also change the content of the manifest file in order to let browsers know that they need to refresh the cache.
All requests to such resources bypass the cache, even if the user is offline.
The wildcard character section specifies fallback pages the browser should use if a resource is inaccessible.
A cache manifest file can have any file extension, but it must be served with the MIME type The cache manifest file is a simple text file that lists the resources the browser should cache for offline access. Entries listed in the cache manifest must have the same scheme, host, and port as the manifest. The "v1" comment in the example above is there for a good reason.
Using an application cache gives an application the following benefits: attribute, unless such pages are explicitly listed in the manifest file itself.
You do not need to list all the pages you want cached in the manifest file, the browser implicitly adds every page that the user visits and that has the attribute set to the application cache.
Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes.
Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision.
Search for updating the manifest mf:
Newlines may be represented by line feed ( space between the two words), followed by zero or more space or tab characters. The remainder of the cache manifest must be comprised of zero or more of the following lines: ) section, each line is a valid URI or IRI reference to a resource to cache (no wildcard characters are allowed in this sections).