I’m building a Chrome extension, manifest version 3, and grappling with declarativeNetRequest.

Desired behavior:

1. User types in something like “go/blah” in their Chrome URL bar
2. The pattern “go/*” triggers my Chrome extension, which can then process “blah” and do something with it

My manifest looks like this:

{
  "name": "...",
  "description": "...",
  "version": "0.1",
  "manifest_version": 3,
  "background": {
    "service_worker": "background.js"
  },
  "host_permissions": [
    "*://*/*"
  ],
  "declarative_net_request": {
    "rule_resources": [
      {
        "id": "ruleset_1",
        "enabled": true,
        "path": "rules.json"
      }
    ]
  },
  "permissions": [
    "declarativeNetRequest",
    "declarativeNetRequestWithHostAccess",
    "declarativeNetRequestFeedback"
  ]
}

Here’s the rule I’m trying to use:

[
    {
      "id": 1,
      "priority": 1,
      "action": {
        "type": "redirect",
        "redirect": { "extensionPath": "/redirect.html" }
      },
      "condition": {
        "urlFilter": "||go/*",
        "resourceTypes": ["main_frame"]
      }
    }
  ]

First problem: this doesn’t trigger when I try to visit a page like “go/blah”. If I change the urlFilter to not have a wildcard, eg blahblah, my Chrome extension does fire correctly

Second problem: even after the urlFilter is fixed, how can I access what filled in the wildcard, ie what came after go/, in a script that’s in redirect.html?