diff --git a/src/lib/serial/connection.ts b/src/lib/serial/connection.ts
index f0196aa1..dde8bd53 100644
--- a/src/lib/serial/connection.ts
+++ b/src/lib/serial/connection.ts
@@ -1,4 +1,4 @@
-import { get, writable } from "svelte/store";
+import { derived, get, writable } from "svelte/store";
 import { CharaDevice, type SerialPortLike } from "$lib/serial/device";
 import type { Chord } from "$lib/serial/chord";
 import type { Writable } from "svelte/store";
@@ -7,12 +7,27 @@ import { persistentWritable } from "$lib/storage";
 import { userPreferences } from "$lib/preferences";
 import { getMeta } from "$lib/meta/meta-storage";
 import type { VersionMeta } from "$lib/meta/types/meta";
+import { serial as serialPolyfill } from "web-serial-polyfill";
 
 export const serialPort = writable<CharaDevice | undefined>();
 
-navigator.serial?.addEventListener("disconnect", async (event) => {
+export const forceWebUSB = persistentWritable("force-webusb", false);
+
+async function onSerialDisconnect() {
   serialPort.set(undefined);
-});
+}
+
+export const serialObject = derived<typeof forceWebUSB, Serial>(
+  forceWebUSB,
+  (forceWebUSB) =>
+    forceWebUSB || !("serial" in navigator)
+      ? (serialPolyfill as any as Serial)
+      : navigator.serial,
+);
+
+if ("serial" in navigator) {
+  navigator.serial.addEventListener("disconnect", onSerialDisconnect);
+}
 
 export interface SerialLogEntry {
   type: "input" | "output" | "system";
diff --git a/src/lib/serial/device.ts b/src/lib/serial/device.ts
index 2a3f0330..9f77419f 100644
--- a/src/lib/serial/device.ts
+++ b/src/lib/serial/device.ts
@@ -7,7 +7,6 @@ import {
   stringifyChordActions,
   stringifyPhrase,
 } from "$lib/serial/chord";
-import { browser } from "$app/environment";
 import { showConnectionFailedDialog } from "$lib/dialogs/connection-failed-dialog";
 import semverGte from "semver/functions/gte";
 
@@ -71,23 +70,8 @@ const KEY_COUNTS = {
   ZERO: 256,
 } as const;
 
-if (
-  browser &&
-  navigator.serial === undefined &&
-  import.meta.env.TAURI_FAMILY !== undefined
-) {
-  await import("./tauri-serial");
-}
-
-if (browser && navigator.serial === undefined && navigator.usb !== undefined) {
-  // @ts-expect-error polyfill
-  navigator.serial = await import("web-serial-polyfill").then(
-    ({ serial }) => serial,
-  );
-}
-
-export async function getViablePorts(): Promise<SerialPort[]> {
-  return navigator.serial.getPorts().then((ports) =>
+export async function getViablePorts(serial: Serial): Promise<SerialPort[]> {
+  return serial.getPorts().then((ports) =>
     ports.filter((it) => {
       const { usbProductId, usbVendorId } = it.getInfo();
       for (const filter of PORT_FILTERS.values()) {
@@ -109,8 +93,8 @@ type LengthArray<T, N extends number, R extends T[] = []> = number extends N
     ? R
     : LengthArray<T, N, [T, ...R]>;
 
-export async function canAutoConnect() {
-  return getViablePorts().then((it) => it.length === 1);
+export async function canAutoConnect(serial: Serial) {
+  return getViablePorts(serial).then((it) => it.length === 1);
 }
 
 async function timeout<T>(promise: Promise<T>, ms: number): Promise<T> {
diff --git a/src/routes/(app)/+layout.svelte b/src/routes/(app)/+layout.svelte
index 22a187b5..32580d95 100644
--- a/src/routes/(app)/+layout.svelte
+++ b/src/routes/(app)/+layout.svelte
@@ -12,7 +12,7 @@
     themeFromSourceColor,
   } from "@material/material-color-utilities";
   import { canAutoConnect, getViablePorts } from "$lib/serial/device";
-  import { initSerial } from "$lib/serial/connection";
+  import { initSerial, serialObject } from "$lib/serial/connection";
   import type { LayoutData } from "./$types";
   import { browser } from "$app/environment";
   import "tippy.js/animations/shift-away.css";
@@ -74,8 +74,12 @@
       webManifestLink = await initPwa();
     }
 
-    if (browser && $userPreferences.autoConnect && (await canAutoConnect())) {
-      const [port] = await getViablePorts();
+    if (
+      browser &&
+      $userPreferences.autoConnect &&
+      (await canAutoConnect($serialObject))
+    ) {
+      const [port] = await getViablePorts($serialObject);
       await initSerial(port!, true);
     }
 
diff --git a/src/routes/(app)/ConnectPopup.svelte b/src/routes/(app)/ConnectPopup.svelte
index 1e8b24e8..57ee2bbd 100644
--- a/src/routes/(app)/ConnectPopup.svelte
+++ b/src/routes/(app)/ConnectPopup.svelte
@@ -1,21 +1,27 @@
 <script lang="ts">
   import LL from "$i18n/i18n-svelte";
   import { preference, userPreferences } from "$lib/preferences";
-  import { initSerial } from "$lib/serial/connection";
+  import {
+    forceWebUSB,
+    initSerial,
+    serialObject,
+  } from "$lib/serial/connection";
   import {
     getPortName,
     PORT_FILTERS,
     type SerialPortLike,
   } from "$lib/serial/device";
   import { showConnectionFailedDialog } from "$lib/dialogs/connection-failed-dialog";
-  import { onMount } from "svelte";
   import { persistentWritable } from "$lib/storage";
+  import { browser } from "$app/environment";
 
   let ports = $state<SerialPort[]>([]);
   let element: HTMLDivElement | undefined = $state();
+  let supportsWebSerial = browser && "serial" in navigator;
+  let supportsWebUSB = browser && "usb" in navigator;
 
-  onMount(() => {
-    refreshPorts();
+  $effect(() => {
+    refreshPorts($serialObject);
   });
 
   let hasDiscoveredAutoConnect = persistentWritable(
@@ -29,8 +35,8 @@
     }
   });
 
-  async function refreshPorts() {
-    ports = await navigator.serial.getPorts();
+  async function refreshPorts(serial: Serial) {
+    ports = await serial.getPorts();
   }
 
   async function connect(port: SerialPortLike, withSync: boolean) {
@@ -46,13 +52,13 @@
     element?.closest<HTMLElement>("[popover]")?.hidePopover();
   }
 
-  async function connectDevice(event: MouseEvent) {
-    const port = await navigator.serial.requestPort({
+  async function connectDevice(event: MouseEvent, serial: Serial) {
+    const port = await serial.requestPort({
       filters: event.shiftKey ? [] : [...PORT_FILTERS.values()],
     });
     if (!port) return;
     closePopover();
-    refreshPorts();
+    refreshPorts(serial);
     connect(port, true);
   }
 </script>
@@ -60,55 +66,79 @@
 <div
   bind:this={element}
   class="device-list"
-  onmouseenter={() => refreshPorts()}
+  onmouseenter={() => refreshPorts($serialObject)}
   role="region"
 >
-  {#if ports.length === 1}
+  {#if supportsWebSerial || supportsWebUSB}
     <fieldset class:promote={!$hasDiscoveredAutoConnect}>
-      <label
-        ><input type="checkbox" use:preference={"autoConnect"} />
-        <div class="title">{$LL.deviceManager.AUTO_CONNECT()}</div>
-      </label>
+      {#if ports.length === 1}
+        <label
+          ><input type="checkbox" use:preference={"autoConnect"} />
+          <div class="title">{$LL.deviceManager.AUTO_CONNECT()}</div>
+        </label>
 
-      <label
-        ><input type="checkbox" use:preference={"backup"} />
-        <div class="title">{@html $LL.backup.AUTO_BACKUP()}</div>
+        <label
+          ><input type="checkbox" use:preference={"backup"} />
+          <div class="title">{@html $LL.backup.AUTO_BACKUP()}</div>
+        </label>
+      {/if}
+
+      <label title="You can try this if you have trouble with the connection."
+        ><input
+          type="checkbox"
+          disabled={!supportsWebSerial}
+          checked={!supportsWebSerial || $forceWebUSB}
+          onchange={(event) => {
+            $forceWebUSB = (event.target as HTMLInputElement).checked;
+          }}
+        />
+        <div class="title">WebUSB Fallback</div>
       </label>
     </fieldset>
-  {/if}
-  {#if ports.length !== 0}
-    <h4>Recent Devices</h4>
-    <div class="devices">
-      <!--
+    {#if ports.length !== 0}
+      <h4>Recent Devices</h4>
+      <div class="devices">
+        <!--
       <div class="device">
         <button onclick={connectCC0}> CC0</button>
       </div>-->
-      {#each ports as port}
-        <div class="device">
-          <button
-            onclick={(event) => {
-              connect(port, !event.shiftKey);
-            }}
-          >
-            {getPortName(port)}</button
-          >
-          <button
-            class="error"
-            onclick={() => {
-              port.forget();
-              refreshPorts();
-            }}><span class="icon">visibility_off</span> Hide</button
-          >
-        </div>
-      {/each}
+        {#each ports as port}
+          <div class="device">
+            <button
+              onclick={(event) => {
+                connect(port, !event.shiftKey);
+              }}
+            >
+              {getPortName(port)}</button
+            >
+            <button
+              class="error"
+              onclick={() => {
+                port.forget();
+                refreshPorts($serialObject);
+              }}><span class="icon">visibility_off</span> Hide</button
+            >
+          </div>
+        {/each}
+      </div>
+    {/if}
+    <div class="pair">
+      <button
+        onclick={(event) => connectDevice(event, $serialObject)}
+        class="primary"><span class="icon">add</span>Connect</button
+      >
+      <!--<a href="/ccos/zero_wasm/"><span class="icon">add</span>Virtual Device</a>-->
     </div>
+    {#if !supportsWebSerial}
+      <p>Browser with limited support detected.</p>
+    {/if}
+  {:else}
+    <p><b>Your browser is missing support for critical features.</b></p>
+    <p>
+      Please use a Chromium-based browser such as Chrome, Edge or Chromium
+      instead.
+    </p>
   {/if}
-  <div class="pair">
-    <button onclick={connectDevice} class="primary"
-      ><span class="icon">add</span>Connect</button
-    >
-    <!--<a href="/ccos/zero_wasm/"><span class="icon">add</span>Virtual Device</a>-->
-  </div>
 </div>
 
 <style lang="scss">
diff --git a/src/routes/(app)/ccos/[device]/[version]/+page.svelte b/src/routes/(app)/ccos/[device]/[version]/+page.svelte
index 69cb7928..ba81b1ed 100644
--- a/src/routes/(app)/ccos/[device]/[version]/+page.svelte
+++ b/src/routes/(app)/ccos/[device]/[version]/+page.svelte
@@ -1,6 +1,6 @@
 <script lang="ts">
   import { downloadBackup } from "$lib/backup/backup";
-  import { initSerial, serialPort } from "$lib/serial/connection";
+  import { initSerial, serialObject, serialPort } from "$lib/serial/connection";
   import { fade, slide } from "svelte/transition";
   import { lt as semverLt } from "semver";
   import type { LoaderOptions, ESPLoader } from "esptool-js";
@@ -95,9 +95,9 @@
     }
   }
 
-  async function connect() {
+  async function connect(serial: Serial) {
     try {
-      const port = await navigator.serial.requestPort();
+      const port = await serial.requestPort();
       await initSerial(port!, true);
       step = 1;
     } catch (e) {
@@ -138,9 +138,9 @@
     step = 4;
   }
 
-  async function espBootloader() {
+  async function espBootloader(serial: Serial) {
     $serialPort?.forget();
-    const port = await navigator.serial.requestPort();
+    const port = await serial.requestPort();
     port.open({ baudRate: 1200 });
   }
 
@@ -172,8 +172,8 @@
     return espLoader;
   }
 
-  async function flashImages() {
-    const port = await navigator.serial.requestPort();
+  async function flashImages(serial: Serial) {
+    const port = await serial.requestPort();
     try {
       const esptool = data.meta.update.esptool!;
       espLoader = await connectEsp(port);
@@ -202,8 +202,8 @@
     }
   }
 
-  async function eraseSPI() {
-    const port = await navigator.serial.requestPort();
+  async function eraseSPI(serial: Serial) {
+    const port = await serial.requestPort();
     try {
       console.log(data.meta);
       const spiFlash = data.meta.spiFlash!;
@@ -314,7 +314,7 @@
       <section>
         <ol>
           <li>
-            <button class="inline-button" onclick={connect}
+            <button class="inline-button" onclick={() => connect($serialObject)}
               ><span class="icon">usb</span>Connect</button
             >
             your device
@@ -367,17 +367,17 @@
         </p>
 
         <div class="esp-buttons">
-          <button onclick={espBootloader}
+          <button onclick={() => espBootloader($serialObject)}
             ><span class="icon">memory</span>ESP Bootloader</button
           >
-          <button onclick={flashImages}
+          <button onclick={() => flashImages($serialObject)}
             ><span class="icon">developer_board</span>Flash Images</button
           >
           <label
             ><input type="checkbox" id="erase" bind:checked={eraseAll} />Erase
             All</label
           >
-          <button onclick={eraseSPI}
+          <button onclick={() => eraseSPI($serialObject)}
             ><span class="icon">developer_board</span>Erase SPI Flash</button
           >
         </div>