Adding the webRequest permission to my manifest file does not give me access to the webRequest WebExtension api in my background page.
From looking at the docs, I see that webRequestBlocking is not supported, but no mention of webRequest not being supported.
I am on macOS 12.1 and Safari 15.2.
Example:
...
"permissions": [
"<all_urls>",
"webRequest"
]
...