diff --git a/src/background/handlers/onBeforeVideoWeaverRequest.ts b/src/background/handlers/onBeforeVideoWeaverRequest.ts
index 9eba3c7..deec2f2 100644
--- a/src/background/handlers/onBeforeVideoWeaverRequest.ts
+++ b/src/background/handlers/onBeforeVideoWeaverRequest.ts
@@ -38,7 +38,7 @@ export default function onBeforeVideoWeaverRequest(
       textLower.includes("https://example.com") &&
       textLower.includes("https://help.twitch.tv/");
     const proxy =
-      details.proxyInfo && details.proxyInfo.type !== "direct"
+      details.proxyInfo && details.proxyInfo.type !== "DIRECT"
         ? getUrlFromProxyInfo(details.proxyInfo)
         : null;
 
diff --git a/src/background/handlers/onResponseStarted.ts b/src/background/handlers/onResponseStarted.ts
index a02b436..e188386 100644
--- a/src/background/handlers/onResponseStarted.ts
+++ b/src/background/handlers/onResponseStarted.ts
@@ -171,7 +171,7 @@ function getProxyFromDetails(
     return getUrlFromProxyInfo(possibleProxies[0]);
   } else {
     const proxyInfo = details.proxyInfo; // Firefox only.
-    if (!proxyInfo || proxyInfo.type === "direct") return null;
+    if (!proxyInfo || proxyInfo.type === "DIRECT") return null;
     return getUrlFromProxyInfo(proxyInfo);
   }
 }
diff --git a/src/common/ts/proxyInfo.ts b/src/common/ts/proxyInfo.ts
index a053a22..9b06313 100644
--- a/src/common/ts/proxyInfo.ts
+++ b/src/common/ts/proxyInfo.ts
@@ -1,18 +1,34 @@
 import { Address6 } from "ip-address";
-import type { ProxyInfo } from "../../types";
+import type { ProxyInfo, ProxyScheme } from "../../types";
 
-export function getProxyInfoFromUrl(
-  url: string
-): ProxyInfo & { type: "http"; host: string; port: number } {
+export const proxySchemes: { [key: string]: ProxyScheme } = {
+  direct: "DIRECT",
+  http: "PROXY",
+  https: "HTTPS",
+  socks: "SOCKS",
+  socks4: "SOCKS4",
+  socks5: "SOCKS5",
+  quic: "QUIC",
+};
+
+export function getProxyInfoFromUrl(url: string) {
+  let protocol = "";
+  if (url.includes("://")) {
+    let [proto, urlWithoutProtocol] = url.split("://");
+    protocol = proto;
+    url = urlWithoutProtocol;
+  }
   const lastIndexOfAt = url.lastIndexOf("@");
-  const hostname = url.substring(lastIndexOfAt + 1, url.length);
+  let hostname = url.substring(lastIndexOfAt + 1, url.length);
   const lastIndexOfColon = getLastIndexOfColon(hostname);
-
+  hostname;
   let host: string | undefined = undefined;
   let port: number | undefined = undefined;
   if (lastIndexOfColon === -1) {
     host = hostname;
-    port = 3128; // Default port
+    if (!protocol) {
+      port = 3128; // Default port
+    }
   } else {
     host = hostname.substring(0, lastIndexOfColon);
     port = Number(hostname.substring(lastIndexOfColon + 1, hostname.length));
@@ -31,7 +47,8 @@ export function getProxyInfoFromUrl(
   }
 
   return {
-    type: "http",
+    type: proxySchemes[protocol] ?? "PROXY",
+    protocol,
     host,
     port,
     username,
diff --git a/src/common/ts/proxySettings.ts b/src/common/ts/proxySettings.ts
index 2269791..d493f5f 100644
--- a/src/common/ts/proxySettings.ts
+++ b/src/common/ts/proxySettings.ts
@@ -92,7 +92,7 @@ function getProxyInfoStringFromUrls(urls: string[]): string {
   return [
     ...urls.map(url => {
       const proxyInfo = getProxyInfoFromUrl(url);
-      return `PROXY ${getUrlFromProxyInfo({
+      return `${proxyInfo.type} ${getUrlFromProxyInfo({
         ...proxyInfo,
         // Don't include username/password in PAC script.
         username: undefined,
diff --git a/src/options/options.ts b/src/options/options.ts
index 078e0b4..640a648 100644
--- a/src/options/options.ts
+++ b/src/options/options.ts
@@ -16,10 +16,9 @@ import sendAdLog from "../common/ts/sendAdLog";
 import store from "../store";
 import getDefaultState from "../store/getDefaultState";
 import type { State } from "../store/types";
-import { KeyOfType, ProxyRequestType } from "../types";
+import { AllowedResult, KeyOfType, ProxyRequestType } from "../types";
 
 //#region Types
-type AllowedResult = [boolean, string?];
 type InsertMode = "append" | "prepend" | "both";
 type StoreStringArrayKey = KeyOfType<typeof store.state, string[]>;
 type ListOptions = {
@@ -323,12 +322,16 @@ function isOptimizedProxyUrlAllowed(url: string): AllowedResult {
     return [false, "TTV LOL PRO v1 proxies are not compatible"];
   }
 
-  if (/^https?:\/\//i.test(url)) {
-    return [false, "Proxy URLs must not contain a protocol (e.g. 'http://')"];
+  const proxyInfo = getProxyInfoFromUrl(url);
+  if (proxyInfo.host.includes("/")) {
+    return [false, "Proxy URLs must not contain a path (e.g. '/path')"];
   }
 
-  if (url.includes("/")) {
-    return [false, "Proxy URLs must not contain a path (e.g. '/path')"];
+  try {
+    const host = url.substring(url.lastIndexOf("@") + 1, url.length);
+    new URL(`http://${host}`); // Throws if the host is invalid.
+  } catch {
+    return [false, `'${url}' is not a valid proxy URL`];
   }
 
   try {
diff --git a/src/types.ts b/src/types.ts
index ca7d7a4..ce657e3 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -3,9 +3,21 @@ export type KeyOfType<T, V> = keyof {
   [P in keyof T as T[P] extends V ? P : never]: any;
 };
 
+export type AllowedResult = [boolean, string?];
+
+// From https://chromium.googlesource.com/chromium/src/+/HEAD/net/docs/proxy.md#proxy-server-schemes
+export type ProxyScheme =
+  | "DIRECT"
+  | "PROXY"
+  | "HTTPS"
+  | "SOCKS"
+  | "SOCKS4"
+  | "SOCKS5"
+  | "QUIC";
+
 // From https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/proxy/ProxyInfo
 export interface ProxyInfo {
-  type: "direct" | "http" | "https" | "socks" | "socks4";
+  type: ProxyScheme;
   host?: string;
   port?: number;
   username?: string;