diff --git a/dist/_locales/en/messages.json b/dist/_locales/en/messages.json
index c65b08a7..3e6a9326 100644
--- a/dist/_locales/en/messages.json
+++ b/dist/_locales/en/messages.json
@@ -1200,6 +1200,15 @@
       }
     }
   },
+  "optionsSyncUsername": {
+    "message": "Username"
+  },
+  "optionsSyncPassword": {
+    "message": "Password"
+  },
+  "optionsSyncUrl": {
+    "message": "URL"
+  },
   "optionsSyncStatusRelogin": {
     "message": "Session expired, please login again."
   },
diff --git a/dist/background/sync-manager.js b/dist/background/sync-manager.js
index cb51498d..e1aafd4e 100644
--- a/dist/background/sync-manager.js
+++ b/dist/background/sync-manager.js
@@ -1,5 +1,5 @@
 /* global API msg */// msg.js
-/* global chromeLocal */// storage-util.js
+/* global chromeLocal chromeSync */// storage-util.js
 /* global compareRevision */// common.js
 /* global iconMan */
 /* global prefs */
@@ -18,6 +18,7 @@ const syncMan = (() => {
     disconnecting: 'disconnecting',
   });
   const STORAGE_KEY = 'sync/state/';
+  const NO_LOGIN = ['webdav'];
   const status = /** @namespace SyncManager.Status */ {
     STATES,
     state: STATES.disconnected,
@@ -85,19 +86,29 @@ const syncMan = (() => {
       return ctrl.put(...args);
     },
 
+    async setDriveOptions(driveName, options) {
+      const key = `secure/sync/driveOptions/${driveName}`;
+      await chromeSync.setValue(key, options);
+    },
+
+    async getDriveOptions(driveName) {
+      const key = `secure/sync/driveOptions/${driveName}`;
+      return await chromeSync.getValue(key) || {};
+    },
+
     async start(name, fromPref = false) {
       if (ready.then) await ready;
       if (!ctrl) await initController();
 
       if (currentDrive) return;
-      currentDrive = getDrive(name);
+      currentDrive = await getDrive(name);
       ctrl.use(currentDrive);
 
       status.state = STATES.connecting;
       status.currentDriveName = currentDrive.name;
       emitStatusChange();
 
-      if (fromPref) {
+      if (fromPref || NO_LOGIN.includes(currentDrive.name)) {
         status.login = true;
       } else {
         try {
@@ -240,11 +251,11 @@ const syncMan = (() => {
     }
   }
 
-  function getDrive(name) {
-    if (name === 'dropbox' || name === 'google' || name === 'onedrive') {
-      return dbToCloud.drive[name]({
-        getAccessToken: () => tokenMan.getToken(name),
-      });
+  async function getDrive(name) {
+    if (name === 'dropbox' || name === 'google' || name === 'onedrive' || name === 'webdav') {
+      const options = await syncMan.getDriveOptions(name);
+      options.getAccessToken = () => tokenMan.getToken(name);
+      return dbToCloud.drive[name](options);
     }
     throw new Error(`unknown cloud name: ${name}`);
   }
diff --git a/dist/options.html b/dist/options.html
index a6170f82..7705accf 100644
--- a/dist/options.html
+++ b/dist/options.html
@@ -199,10 +199,27 @@
                 <option value="dropbox">Dropbox</option>
                 <option value="google">Google Drive</option>
                 <option value="onedrive">OneDrive</option>
+                <option value="webdav">WebDAV</option>
               </select>
               <svg class="svg-icon select-arrow"><use xlink:href="#svg-icon-select-arrow"/></svg>
             </div>
           </div>
+          <fieldset class="drive-options">
+            <div class="webdav-options" data-drive="webdav">
+              <label class="url">
+                <span i18n-text="optionsSyncUrl"></span>
+                <input type="text" data-option="url">
+              </label>
+              <label class="username">
+                <span i18n-text="optionsSyncUsername"></span>
+                <input type="text" data-option="username">
+              </label>
+              <label class="password">
+                <span i18n-text="optionsSyncPassword"></span>
+                <input type="password" data-option="password">
+              </label>
+            </div>
+          </fieldset>
           <div class="actions">
             <button type="button" class="connect" i18n-text="optionsSyncConnect"></button>
             <button type="button" class="disconnect" i18n-text="optionsSyncDisconnect"></button>
diff --git a/dist/options/options.css b/dist/options/options.css
index 283522bd..8ace53b5 100644
--- a/dist/options/options.css
+++ b/dist/options/options.css
@@ -163,7 +163,7 @@ label > :first-child {
 }
 
 label:not([disabled]),
-label:not([disabled]) :not([type="number"]) {
+label:not([disabled]) :not([type="number"]):not([type="text"]):not([type="password"]) {
   cursor: pointer;
 }
 
@@ -437,7 +437,25 @@ input[type="radio"].radio:checked::after {
 .sync-status::first-letter {
   text-transform: uppercase;
 }
-
+.sync-options .drive-options {
+  margin: 0;
+  padding: 0;
+  border: 0;
+}
+.drive-options > :not([hidden]) {
+  display: table;
+  width: 100%;
+}
+.drive-options > * > label {
+  display: table-row;
+}
+.drive-options > * > label > * {
+  display: table-cell;
+}
+.drive-options > * input {
+  width: 100%;
+  box-sizing: border-box;
+}
 .sync-options .actions button {
   margin-top: .5em;
 }
diff --git a/dist/options/options.js b/dist/options/options.js
index 9d8c061e..fbaa7f12 100644
--- a/dist/options/options.js
+++ b/dist/options/options.js
@@ -96,6 +96,7 @@ document.onclick = e => {
   const elSyncNow = $('.sync-options .sync-now');
   const elStatus = $('.sync-options .sync-status');
   const elLogin = $('.sync-options .sync-login');
+  const elDriveOptions = $('.sync-options .drive-options');
   /** @type {Sync.Status} */
   let status = {};
   msg.onExtension(e => {
@@ -108,7 +109,10 @@ document.onclick = e => {
 
   elCloud.on('change', updateButtons);
   for (const [btn, fn] of [
-    [elStart, () => API.sync.start(elCloud.value)],
+    [elStart, async () => {
+      await API.sync.setDriveOptions(elCloud.value, getDriveOptions());
+      await API.sync.start(elCloud.value);
+    }],
     [elStop, API.sync.stop],
     [elSyncNow, API.sync.syncNow],
     [elLogin, async () => {
@@ -123,12 +127,26 @@ document.onclick = e => {
     });
   }
 
+  function getDriveOptions() {
+    const result = {};
+    for (const el of $$(`[data-drive=${elCloud.value}] [data-option]`)) {
+      result[el.dataset.option] = el.value;
+    }
+    return result;
+  }
+
+  function setDriveOptions(options) {
+    for (const el of $$(`[data-drive=${elCloud.value}] [data-option]`)) {
+      el.value = options[el.dataset.option] || '';
+    }
+  }
+
   function setStatus(newStatus) {
     status = newStatus;
     updateButtons();
   }
 
-  function updateButtons() {
+  async function updateButtons() {
     const {state, STATES} = status;
     const isConnected = state === STATES.connected;
     const isDisconnected = state === STATES.disconnected;
@@ -137,6 +155,7 @@ document.onclick = e => {
     }
     for (const [el, enable] of [
       [elCloud, isDisconnected],
+      [elDriveOptions, isDisconnected],
       [elStart, isDisconnected && elCloud.value !== 'none'],
       [elStop, isConnected && !status.syncing],
       [elSyncNow, isConnected && !status.syncing && status.login],
@@ -145,6 +164,10 @@ document.onclick = e => {
     }
     elStatus.textContent = getStatusText();
     elLogin.hidden = !isConnected || status.login;
+    for (const el of elDriveOptions.children) {
+      el.hidden = el.dataset.drive !== elCloud.value;
+    }
+    setDriveOptions(await API.sync.getDriveOptions(elCloud.value));
   }
 
   function getStatusText() {