diff --git a/radicale/web/internal_data/index.html b/radicale/web/internal_data/index.html
index baa242c7..cb813508 100644
--- a/radicale/web/internal_data/index.html
+++ b/radicale/web/internal_data/index.html
@@ -280,6 +280,14 @@
             name="newshare_permissions"><label for="newshare_attr_permissions_ro">Readonly</label>
           <input type="radio" data-name="permissions" id="newshare_attr_permissions_rw"
             name="newshare_permissions" /><label for="newshare_attr_permissions_rw">Read/Write</label>
+          <br />
+          <input type="radio" data-name="properties_write" id="newshare_attr_properties_write_deny"
+            name="newshare_properties_write"><label for="newshare_attr_properties_write_deny">Deny</label>
+          <input type="radio" data-name="properties_write" id="newshare_attr_properties_write_allow"
+            name="newshare_properties_write"><label for="newshare_attr_properties_write_allow">Allow Properties
+            write</label>
+          <p data-name="token_write_warning" class="red hidden">WARNING: This allows everyone who knows the URL to make
+            changes.</p>
         </details>
         <details data-name="conversions" class="hidden">
           <summary>Conversions</summary>
diff --git a/radicale/web/internal_data/js/models/collection.js b/radicale/web/internal_data/js/models/collection.js
index 1e51224c..05474aa8 100644
--- a/radicale/web/internal_data/js/models/collection.js
+++ b/radicale/web/internal_data/js/models/collection.js
@@ -99,6 +99,18 @@ export class CollectionType {
     }
 }
 
+export class Permission {
+    // Private Fields
+    static #_WRITE_PROPERTIES = "D:write-properties";
+    static #_SHARE_MAP = "RADICALE:share-map";
+    static #_SHARE_TOKEN = "RADICALE:share-token";
+
+    // Accessors for "get" functions only (no "set" functions)
+    static get WRITE_PROPERTIES() { return this.#_WRITE_PROPERTIES; }
+    static get SHARE_MAP() { return this.#_SHARE_MAP; }
+    static get SHARE_TOKEN() { return this.#_SHARE_TOKEN; }
+}
+
 
 export class Collection {
     /**
@@ -123,4 +135,11 @@ export class Collection {
         this.size = size;
         this.permissions = permissions;
     }
+
+    has_permission(/** @type {string} */ permission) {
+        if (!this.permissions) {
+            return false;
+        }
+        return this.permissions.includes(permission);
+    }
 }
\ No newline at end of file
diff --git a/radicale/web/internal_data/js/scenes/CollectionsScene.js b/radicale/web/internal_data/js/scenes/CollectionsScene.js
index b4d85f07..abdc2b82 100644
--- a/radicale/web/internal_data/js/scenes/CollectionsScene.js
+++ b/radicale/web/internal_data/js/scenes/CollectionsScene.js
@@ -21,7 +21,7 @@
 
 import { delete_collection } from "../api/api.js";
 import { get_auth_header } from "../api/common.js";
-import { Collection, CollectionType } from "../models/collection.js";
+import { Collection, CollectionType, Permission } from "../models/collection.js";
 import { collectionsCache } from "../utils/collections_cache.js";
 import { ErrorHandler } from "../utils/error.js";
 import { bytesToHumanReadable, get_element, get_element_by_id } from "../utils/misc.js";
@@ -189,10 +189,7 @@ export class CollectionsScene {
             });
 
             let share_option = get_element(node, "[data-name=shareoption]");
-            let can_share = collection.permissions && (
-                collection.permissions.includes("RADICALE:share-map") ||
-                collection.permissions.includes("RADICALE:share-token")
-            );
+            let can_share = collection.has_permission(Permission.SHARE_MAP) || collection.has_permission(Permission.SHARE_TOKEN);
             if (share_option) {
                 if (can_share) {
                     share_option.classList.remove("hidden");
diff --git a/radicale/web/internal_data/js/scenes/CreateEditShareScene.js b/radicale/web/internal_data/js/scenes/CreateEditShareScene.js
index 4a0d68b3..f2f869ee 100644
--- a/radicale/web/internal_data/js/scenes/CreateEditShareScene.js
+++ b/radicale/web/internal_data/js/scenes/CreateEditShareScene.js
@@ -20,7 +20,7 @@
  */
 
 import { Share, add_share_by_map, add_share_by_token, get_property_key, update_share_by_map, update_share_by_token } from "../api/sharing.js";
-import { CollectionType } from "../models/collection.js";
+import { CollectionType, Permission } from "../models/collection.js";
 import { collectionsCache } from "../utils/collections_cache.js";
 import { ErrorHandler } from "../utils/error.js";
 import { FormValidator, validate_href, validate_non_empty, validate_not_empty_or_equals } from "../utils/form_validator.js";
@@ -56,6 +56,9 @@ export class CreateEditShareScene {
         this._hidden_checkbox = /** @type {HTMLInputElement} */ (get_element(this._html_scene, "[data-name=hidden]"));
         this._permissions_ro_radio = /** @type {HTMLInputElement} */ (get_element_by_id("newshare_attr_permissions_ro"));
         this._permissions_rw_radio = /** @type {HTMLInputElement} */ (get_element_by_id("newshare_attr_permissions_rw"));
+        this._properties_write_allow = /** @type {HTMLInputElement} */ (get_element_by_id("newshare_attr_properties_write_allow"));
+        this._properties_write_deny = /** @type {HTMLInputElement} */ (get_element_by_id("newshare_attr_properties_write_deny"));
+        this._token_write_warning = /** @type {HTMLElement} */ (get_element(this._html_scene, "[data-name=token_write_warning]"));
         this._conversions_details = /** @type {HTMLDetailsElement} */ (get_element(this._html_scene, "[data-name=conversions]"));
         this._conversions_container = get_element(this._html_scene, "[data-name=conversions_container]");
 
@@ -103,16 +106,32 @@ export class CreateEditShareScene {
         return checked ? checked.value : "none";
     }
 
+    _on_permissions_change() {
+        if (this._shareType === "token") {
+            if (this._permissions_rw_radio.checked || this._properties_write_allow.checked) {
+                this._token_write_warning.classList.remove("hidden");
+            } else {
+                this._token_write_warning.classList.add("hidden");
+            }
+        } else {
+            this._token_write_warning.classList.add("hidden");
+        }
+    }
+
     _on_conversion_change() {
         let conversion = this._get_selected_conversion();
         if (conversion != "none") {
             this._permissions_ro_radio.disabled = true;
             this._permissions_rw_radio.disabled = true;
+            this._properties_write_allow.disabled = true;
+            this._properties_write_deny.disabled = true;
             this._enabled_checkbox.checked = true;
             this._hidden_checkbox.checked = false;
         } else {
             this._permissions_ro_radio.disabled = false;
             this._permissions_rw_radio.disabled = false;
+            this._properties_write_allow.disabled = false;
+            this._properties_write_deny.disabled = false;
         }
         if (this._shareType === "map") {
             this._map_validator.validate();
@@ -140,7 +159,10 @@ export class CreateEditShareScene {
             let enabled_by_owner = is_conversion ? true : this._enabled_checkbox.checked;
             let hidden_by_owner = is_conversion ? false : this._hidden_checkbox.checked;
             let permissions = is_conversion ? "r" : (this._permissions_rw_radio.checked ? "rw" : "r");
-            if (this._shareType === "token") {
+            let allowPropertiesWrite = this._properties_write_allow.checked;
+            if (allowPropertiesWrite) {
+                permissions = permissions + "P";
+            } else {
                 permissions = permissions + "p";
             }
             /** @type {string} */ let conversion_value = conversion;
@@ -221,6 +243,12 @@ export class CreateEditShareScene {
         this._cancel_btn.onclick = () => this._oncancel();
         this._form.onsubmit = () => this._onsubmit();
 
+        let onChangeCallback = () => this._on_permissions_change();
+        this._permissions_ro_radio.addEventListener("change", onChangeCallback);
+        this._permissions_rw_radio.addEventListener("change", onChangeCallback);
+        this._properties_write_allow.addEventListener("change", onChangeCallback);
+        this._properties_write_deny.addEventListener("change", onChangeCallback);
+
         /** @type {HTMLHeadingElement} */ let title = /** @type {HTMLHeadingElement} */ (get_element(this._html_scene, "h1"));
         title.textContent = this._edit ? "Edit Share" : "New Share";
         this._submit_btn.textContent = this._edit ? "Save" : "Create";
@@ -230,6 +258,18 @@ export class CreateEditShareScene {
         this._enabled_checkbox.checked = (this._edit && this._share && this._share.EnabledByOwner !== null) ? this._share.EnabledByOwner : true;
         this._hidden_checkbox.checked = (this._edit && this._share && this._share.HiddenByOwner !== null) ? this._share.HiddenByOwner : false;
 
+        let hasWriteProperties = this._collection.has_permission(Permission.WRITE_PROPERTIES);
+
+        if (this._edit || this._shareType === "map") {
+            if (hasWriteProperties) {
+                this._properties_write_allow.checked = true;
+            } else {
+                this._properties_write_deny.checked = true;
+            }
+        } else {
+            this._properties_write_deny.checked = true;
+        }
+
         let initial_conversion = (this._edit && this._share && this._share.Conversion) ? this._share.Conversion : "none";
 
         collectionsCache.getServerFeatures(this._user, this._password, this._errorHandler.setError, (features) => {
@@ -363,6 +403,7 @@ export class CreateEditShareScene {
             this._sharemapfields.classList.add("hidden");
             this._errorHandler.clearError();
         }
+        this._on_permissions_change();
     }
 
     hide() {
diff --git a/radicale/web/internal_data/js/scenes/ShareCollectionScene.js b/radicale/web/internal_data/js/scenes/ShareCollectionScene.js
index d8b71d08..676ab49d 100644
--- a/radicale/web/internal_data/js/scenes/ShareCollectionScene.js
+++ b/radicale/web/internal_data/js/scenes/ShareCollectionScene.js
@@ -24,7 +24,7 @@ import {
   delete_share_by_token,
   reload_sharing_list,
 } from "../api/sharing.js";
-import { Collection } from "../models/collection.js";
+import { Collection, Permission } from "../models/collection.js";
 
 import { ErrorHandler } from "../utils/error.js";
 import { get_element, get_element_by_id } from "../utils/misc.js";
@@ -88,8 +88,8 @@ export class ShareCollectionScene {
     });
     this._cancel_btn.onclick = () => this._oncancel();
 
-    let can_share_by_token = this._collection.permissions && this._collection.permissions.includes("RADICALE:share-token");
-    let can_share_by_map = this._collection.permissions && this._collection.permissions.includes("RADICALE:share-map");
+    let can_share_by_token = this._collection.has_permission(Permission.SHARE_TOKEN);
+    let can_share_by_map = this._collection.has_permission(Permission.SHARE_MAP);
 
     if (can_share_by_token) {
       if (this._share_by_token_btn) {