Merge pull request #19425 from calixteman/signature_save

[Editor] Add the possibility to compress/decompress the signature data in  order to store them in the logins storage in Firefox (bug 1946171)

src/display/editor/drawers/signaturedraw.js

@@ -13,10 +13,14 @@
  * limitations under the License.
  */
 
+import { fromBase64Util, toBase64Util, warn } from "../../../shared/util.js";
 import { ContourDrawOutline } from "./contour.js";
 import { InkDrawOutline } from "./inkdraw.js";
 import { Outline } from "./outline.js";
 
+const BASE_HEADER_LENGTH = 8;
+const POINTS_PROPERTIES_NUMBER = 3;
+
 /**
  * Basic text editor in order to create a Signature annotation.
  */
@@ -607,12 +611,14 @@ class SignatureExtractor {
     const ratio = Math.min(pageWidth / width, pageHeight / height);
     const xScale = ratio / pageWidth;
     const yScale = ratio / pageHeight;
+    const newCurves = [];
 
     for (const { points } of curves) {
       const reducedPoints = mustSmooth ? this.#douglasPeucker(points) : points;
       if (!reducedPoints) {
         continue;
       }
+      newCurves.push(reducedPoints);
 
       const len = reducedPoints.length;
       const newPoints = new Float32Array(len);
@@ -660,7 +666,185 @@ class SignatureExtractor {
       innerMargin
     );
 
-    return outline;
+    return { outline, newCurves, areContours, thickness, width, height };
+  }
+
+  static async compressSignature({
+    outlines,
+    areContours,
+    thickness,
+    width,
+    height,
+  }) {
+    // We create a single array containing all the outlines.
+    // The format is the following:
+    // - 4 bytes: data length.
+    // - 4 bytes: version.
+    // - 4 bytes: width.
+    // - 4 bytes: height.
+    // - 4 bytes: 0 if it's a contour, 1 if it's an ink.
+    // - 4 bytes: thickness.
+    // - 4 bytes: number of drawings.
+    // - 4 bytes: size of the buffer containing the diff of the coordinates.
+    // - 4 bytes: number of points in the first drawing.
+    // - 4 bytes: x coordinate of the first point.
+    // - 4 bytes: y coordinate of the first point.
+    // - 4 bytes: number of points in the second drawing.
+    // - 4 bytes: x coordinate of the first point.
+    // - 4 bytes: y coordinate of the first point.
+    // - ...
+    // - The buffer containing the diff of the coordinates.
+
+    // The coordinates are supposed to be positive integers.
+
+    // We also compute the min and max difference between two points.
+    // This will help us to determine the type of the buffer (Int8, Int16 or
+    // Int32) in order to minimize the amount of data we have.
+    let minDiff = Infinity;
+    let maxDiff = -Infinity;
+    let outlinesLength = 0;
+    for (const points of outlines) {
+      outlinesLength += points.length;
+      for (let i = 2, ii = points.length; i < ii; i++) {
+        const dx = points[i] - points[i - 2];
+        minDiff = Math.min(minDiff, dx);
+        maxDiff = Math.max(maxDiff, dx);
+      }
+    }
+
+    let bufferType;
+    if (minDiff >= -128 && maxDiff <= 127) {
+      bufferType = Int8Array;
+    } else if (minDiff >= -32768 && maxDiff <= 32767) {
+      bufferType = Int16Array;
+    } else {
+      bufferType = Int32Array;
+    }
+
+    const len = outlines.length;
+    const headerLength = BASE_HEADER_LENGTH + POINTS_PROPERTIES_NUMBER * len;
+    const header = new Uint32Array(headerLength);
+
+    let offset = 0;
+    header[offset++] =
+      headerLength * Uint32Array.BYTES_PER_ELEMENT +
+      (outlinesLength - 2 * len) * bufferType.BYTES_PER_ELEMENT;
+    header[offset++] = 0; // Version.
+    header[offset++] = width;
+    header[offset++] = height;
+    header[offset++] = areContours ? 0 : 1;
+    header[offset++] = Math.max(0, Math.floor(thickness ?? 0));
+    header[offset++] = len;
+    header[offset++] = bufferType.BYTES_PER_ELEMENT;
+    for (const points of outlines) {
+      header[offset++] = points.length - 2;
+      header[offset++] = points[0];
+      header[offset++] = points[1];
+    }
+
+    const cs = new CompressionStream("deflate-raw");
+    const writer = cs.writable.getWriter();
+    await writer.ready;
+
+    writer.write(header);
+    const BufferCtor = bufferType.prototype.constructor;
+    for (const points of outlines) {
+      const diffs = new BufferCtor(points.length - 2);
+      for (let i = 2, ii = points.length; i < ii; i++) {
+        diffs[i - 2] = points[i] - points[i - 2];
+      }
+      writer.write(diffs);
+    }
+
+    writer.close();
+
+    const buf = await new Response(cs.readable).arrayBuffer();
+    const bytes = new Uint8Array(buf);
+
+    return toBase64Util(bytes);
+  }
+
+  static async decompressSignature(signatureData) {
+    try {
+      const bytes = fromBase64Util(signatureData);
+      const { readable, writable } = new DecompressionStream("deflate-raw");
+      const writer = writable.getWriter();
+      await writer.ready;
+
+      // We can't await writer.write() because it'll block until the reader
+      // starts which happens few lines below.
+      writer
+        .write(bytes)
+        .then(async () => {
+          await writer.ready;
+          await writer.close();
+        })
+        .catch(() => {});
+
+      let data = null;
+      let offset = 0;
+      for await (const chunk of readable) {
+        data ||= new Uint8Array(new Uint32Array(chunk.buffer)[0]);
+        data.set(chunk, offset);
+        offset += chunk.length;
+      }
+
+      // We take a bit too much data for the header but it's fine.
+      const header = new Uint32Array(data.buffer, 0, data.length >> 2);
+      const version = header[1];
+      if (version !== 0) {
+        throw new Error(`Invalid version: ${version}`);
+      }
+      const width = header[2];
+      const height = header[3];
+      const areContours = header[4] === 0;
+      const thickness = header[5];
+      const numberOfDrawings = header[6];
+      const bufferType = header[7];
+      const outlines = [];
+      const diffsOffset =
+        (BASE_HEADER_LENGTH + POINTS_PROPERTIES_NUMBER * numberOfDrawings) *
+        Uint32Array.BYTES_PER_ELEMENT;
+      let diffs;
+
+      switch (bufferType) {
+        case Int8Array.BYTES_PER_ELEMENT:
+          diffs = new Int8Array(data.buffer, diffsOffset);
+          break;
+        case Int16Array.BYTES_PER_ELEMENT:
+          diffs = new Int16Array(data.buffer, diffsOffset);
+          break;
+        case Int32Array.BYTES_PER_ELEMENT:
+          diffs = new Int32Array(data.buffer, diffsOffset);
+          break;
+      }
+
+      offset = 0;
+      for (let i = 0; i < numberOfDrawings; i++) {
+        const len = header[POINTS_PROPERTIES_NUMBER * i + BASE_HEADER_LENGTH];
+        const points = new Float32Array(len + 2);
+        outlines.push(points);
+
+        for (let j = 0; j < POINTS_PROPERTIES_NUMBER - 1; j++) {
+          points[j] =
+            header[POINTS_PROPERTIES_NUMBER * i + BASE_HEADER_LENGTH + j + 1];
+        }
+        for (let j = 0; j < len; j++) {
+          points[j + 2] = points[j] + diffs[offset++];
+        }
+      }
+
+      return {
+        areContours,
+        thickness,
+        outlines,
+        width,
+        height,
+      };
+    } catch (e) {
+      warn(`decompressSignature: ${e}`);
+      return null;
+    }
   }
 }
 

src/display/editor/signature.js

@@ -72,6 +72,7 @@ class SignatureEditor extends DrawingEditor {
     super({ ...params, mustBeCommitted: true, name: "signatureEditor" });
     this._willKeepAspectRatio = true;
     this._description = "";
+    this._signatureUUID = null;
   }
 
   /** @inheritdoc */

src/pdf.js

@@ -30,6 +30,7 @@ import {
   AnnotationType,
   createValidAbsoluteUrl,
   FeatureTest,
+  getUuid,
   ImageKind,
   InvalidPDFException,
   normalizeUnicode,
@@ -72,6 +73,7 @@ import { DOMSVGFactory } from "./display/svg_factory.js";
 import { DrawLayer } from "./display/draw_layer.js";
 import { GlobalWorkerOptions } from "./display/worker_options.js";
 import { HighlightOutliner } from "./display/editor/drawers/highlight.js";
+import { SignatureExtractor } from "./display/editor/drawers/signaturedraw.js";
 import { TextLayer } from "./display/text_layer.js";
 import { TouchManager } from "./display/touch_manager.js";
 import { XfaLayer } from "./display/xfa_layer.js";
@@ -108,6 +110,7 @@ export {
   getDocument,
   getFilenameFromUrl,
   getPdfFilenameFromUrl,
+  getUuid,
   getXfaPageViewport,
   GlobalWorkerOptions,
   ImageKind,
@@ -128,6 +131,7 @@ export {
   ResponseException,
   setLayerDimensions,
   shadow,
+  SignatureExtractor,
   stopEvent,
   SupportedImageMimeTypes,
   TextLayer,

test/unit/editor_spec.js

@@ -14,6 +14,7 @@
  */
 
 import { CommandManager } from "../../src/display/editor/tools.js";
+import { SignatureExtractor } from "../../src/display/editor/drawers/signaturedraw.js";
 
 describe("editor", function () {
   describe("Command Manager", function () {
@@ -90,4 +91,51 @@ describe("editor", function () {
     manager.add({ ...makeDoUndo(5), mustExec: true });
     expect(x).toEqual(11);
   });
+
+  it("should check signature compression/decompression", async () => {
+    let gen = n => new Float32Array(crypto.getRandomValues(new Uint16Array(n)));
+    let outlines = [102, 28, 254, 4536, 10, 14532, 512].map(gen);
+    const signature = {
+      outlines,
+      areContours: false,
+      thickness: 1,
+      width: 123,
+      height: 456,
+    };
+    let compressed = await SignatureExtractor.compressSignature(signature);
+    let decompressed = await SignatureExtractor.decompressSignature(compressed);
+    expect(decompressed).toEqual(signature);
+
+    signature.thickness = 2;
+    compressed = await SignatureExtractor.compressSignature(signature);
+    decompressed = await SignatureExtractor.decompressSignature(compressed);
+    expect(decompressed).toEqual(signature);
+
+    signature.areContours = true;
+    compressed = await SignatureExtractor.compressSignature(signature);
+    decompressed = await SignatureExtractor.decompressSignature(compressed);
+    expect(decompressed).toEqual(signature);
+
+    // Numbers are small enough to be compressed with Uint8Array.
+    gen = n =>
+      new Float32Array(
+        crypto.getRandomValues(new Uint8Array(n)).map(x => x / 10)
+      );
+    outlines = [100, 200, 300, 10, 80].map(gen);
+    signature.outlines = outlines;
+    compressed = await SignatureExtractor.compressSignature(signature);
+    decompressed = await SignatureExtractor.decompressSignature(compressed);
+    expect(decompressed).toEqual(signature);
+
+    // Numbers are large enough to be compressed with Uint16Array.
+    gen = n =>
+      new Float32Array(
+        crypto.getRandomValues(new Uint16Array(n)).map(x => x / 10)
+      );
+    outlines = [100, 200, 300, 10, 80].map(gen);
+    signature.outlines = outlines;
+    compressed = await SignatureExtractor.compressSignature(signature);
+    decompressed = await SignatureExtractor.decompressSignature(compressed);
+    expect(decompressed).toEqual(signature);
+  });
 });

test/unit/pdf_spec.js

@@ -21,6 +21,7 @@ import {
   AnnotationType,
   createValidAbsoluteUrl,
   FeatureTest,
+  getUuid,
   ImageKind,
   InvalidPDFException,
   normalizeUnicode,
@@ -62,6 +63,7 @@ import { ColorPicker } from "../../src/display/editor/color_picker.js";
 import { DOMSVGFactory } from "../../src/display/svg_factory.js";
 import { DrawLayer } from "../../src/display/draw_layer.js";
 import { GlobalWorkerOptions } from "../../src/display/worker_options.js";
+import { SignatureExtractor } from "../../src/display/editor/drawers/signaturedraw.js";
 import { TextLayer } from "../../src/display/text_layer.js";
 import { TouchManager } from "../../src/display/touch_manager.js";
 import { XfaLayer } from "../../src/display/xfa_layer.js";
@@ -85,6 +87,7 @@ const expectedAPI = Object.freeze({
   getDocument,
   getFilenameFromUrl,
   getPdfFilenameFromUrl,
+  getUuid,
   getXfaPageViewport,
   GlobalWorkerOptions,
   ImageKind,
@@ -105,6 +108,7 @@ const expectedAPI = Object.freeze({
   ResponseException,
   setLayerDimensions,
   shadow,
+  SignatureExtractor,
   stopEvent,
   SupportedImageMimeTypes,
   TextLayer,

web/app.js

@@ -461,13 +461,15 @@ const PDFViewerApplication = {
       this.editorUndoBar = new EditorUndoBar(appConfig.editorUndoBar, eventBus);
     }
 
-    const signatureManager = appConfig.addSignatureDialog
-      ? new SignatureManager(
-          appConfig.addSignatureDialog,
-          this.overlayManager,
-          this.l10n
-        )
-      : null;
+    const signatureManager =
+      AppOptions.get("enableSignatureEditor") && appConfig.addSignatureDialog
+        ? new SignatureManager(
+            appConfig.addSignatureDialog,
+            this.overlayManager,
+            this.l10n,
+            externalServices.createSignatureStorage()
+          )
+        : null;
 
     const enableHWA = AppOptions.get("enableHWA");
     const pdfViewer = new PDFViewer({

web/chromecom.js

@@ -19,8 +19,10 @@ import { BaseExternalServices } from "./external_services.js";
 import { BasePreferences } from "./preferences.js";
 import { GenericL10n } from "./genericl10n.js";
 import { GenericScripting } from "./generic_scripting.js";
+import { SignatureStorage } from "./generic_signature_storage.js";
 
 // These strings are from chrome/app/resources/generated_resources_*.xtb.
+// eslint-disable-next-line sort-imports
 import i18nFileAccessLabels from "./chrome-i18n-allow-access-to-file-urls.json" with { type: "json" };
 
 if (typeof PDFJSDev === "undefined" || !PDFJSDev.test("CHROME")) {
@@ -419,6 +421,10 @@ class ExternalServices extends BaseExternalServices {
   createScripting() {
     return new GenericScripting(AppOptions.get("sandboxBundleSrc"));
   }
+
+  createSignatureStorage() {
+    return new SignatureStorage();
+  }
 }
 
 class MLManager {

web/external_services.js

@@ -44,6 +44,10 @@ class BaseExternalServices {
     throw new Error("Not implemented: createScripting");
   }
 
+  createSignatureStorage() {
+    throw new Error("Not implemented: createSignatureStorage");
+  }
+
   updateEditorStates(data) {
     throw new Error("Not implemented: updateEditorStates");
   }

web/firefoxcom.js

@@ -495,6 +495,72 @@ class MLManager {
   }
 }
 
+class SignatureStorage {
+  #signatures = null;
+
+  #handleSignature(data) {
+    return FirefoxCom.requestAsync("handleSignature", data);
+  }
+
+  async getAll() {
+    if (!this.#signatures) {
+      this.#signatures = Object.create(null);
+      const data = await this.#handleSignature({ action: "get" });
+      if (data) {
+        for (const { uuid, description, signatureData } of data) {
+          this.#signatures[uuid] = { description, signatureData };
+        }
+      }
+    }
+    return this.#signatures;
+  }
+
+  async isFull() {
+    // We want to store at most 5 signatures.
+    return Object.keys(await this.getAll()).length === 5;
+  }
+
+  async create(data) {
+    if (await this.isFull()) {
+      return null;
+    }
+    const uuid = await this.#handleSignature({
+      action: "create",
+      ...data,
+    });
+    if (!uuid) {
+      return null;
+    }
+    this.#signatures[uuid] = data;
+    return uuid;
+  }
+
+  async delete(uuid) {
+    const signatures = await this.getAll();
+    if (!signatures[uuid]) {
+      return false;
+    }
+    if (await this.#handleSignature({ action: "delete", uuid })) {
+      delete signatures[uuid];
+      return true;
+    }
+    return false;
+  }
+
+  async update(uuid, data) {
+    const signatures = await this.getAll();
+    const oldData = signatures[uuid];
+    if (!oldData) {
+      return false;
+    }
+    if (await this.#handleSignature({ action: "update", uuid, ...data })) {
+      Object.assign(oldData, data);
+      return true;
+    }
+    return false;
+  }
+}
+
 class ExternalServices extends BaseExternalServices {
   updateFindControlState(data) {
     FirefoxCom.request("updateFindControlState", data);
@@ -581,6 +647,10 @@ class ExternalServices extends BaseExternalServices {
     return FirefoxScripting;
   }
 
+  createSignatureStorage() {
+    return new SignatureStorage();
+  }
+
   dispatchGlobalEvent(event) {
     FirefoxCom.request("dispatchGlobalEvent", event);
   }

web/generic_signature_storage.js

@@ -0,0 +1,76 @@
+/* Copyright 2025 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { getUuid } from "pdfjs-lib";
+
+class SignatureStorage {
+  // TODO: Encrypt the data in using a password and add a UI for entering it.
+  // We could use the Web Crypto API for this (see https://bradyjoslin.com/blog/encryption-webcrypto/
+  // for an example).
+
+  #signatures = null;
+
+  #save() {
+    localStorage.setItem("pdfjs.signature", JSON.stringify(this.#signatures));
+  }
+
+  async getAll() {
+    if (!this.#signatures) {
+      const data = localStorage.getItem("pdfjs.signature");
+      this.#signatures = data ? JSON.parse(data) : Object.create(null);
+    }
+    return this.#signatures;
+  }
+
+  async isFull() {
+    return Object.keys(await this.getAll()).length === 5;
+  }
+
+  async create(data) {
+    if (await this.isFull()) {
+      return null;
+    }
+    const uuid = getUuid();
+    this.#signatures[uuid] = data;
+    this.#save();
+
+    return uuid;
+  }
+
+  async delete(uuid) {
+    const signatures = await this.getAll();
+    if (!signatures[uuid]) {
+      return false;
+    }
+    delete signatures[uuid];
+    this.#save();
+
+    return true;
+  }
+
+  async update(uuid, data) {
+    const signatures = await this.getAll();
+    const oldData = signatures[uuid];
+    if (!oldData) {
+      return false;
+    }
+    Object.assign(oldData, data);
+    this.#save();
+
+    return true;
+  }
+}
+
+export { SignatureStorage };

web/genericcom.js

@@ -18,6 +18,7 @@ import { BaseExternalServices } from "./external_services.js";
 import { BasePreferences } from "./preferences.js";
 import { GenericL10n } from "./genericl10n.js";
 import { GenericScripting } from "./generic_scripting.js";
+import { SignatureStorage } from "./generic_signature_storage.js";
 
 if (typeof PDFJSDev !== "undefined" && !PDFJSDev.test("GENERIC")) {
   throw new Error(
@@ -45,6 +46,10 @@ class ExternalServices extends BaseExternalServices {
   createScripting() {
     return new GenericScripting(AppOptions.get("sandboxBundleSrc"));
   }
+
+  createSignatureStorage() {
+    return new SignatureStorage();
+  }
 }
 
 class MLManager {

web/pdfjs.js

@@ -32,6 +32,7 @@ const {
   getDocument,
   getFilenameFromUrl,
   getPdfFilenameFromUrl,
+  getUuid,
   getXfaPageViewport,
   GlobalWorkerOptions,
   ImageKind,
@@ -52,6 +53,7 @@ const {
   ResponseException,
   setLayerDimensions,
   shadow,
+  SignatureExtractor,
   stopEvent,
   SupportedImageMimeTypes,
   TextLayer,
@@ -81,6 +83,7 @@ export {
   getDocument,
   getFilenameFromUrl,
   getPdfFilenameFromUrl,
+  getUuid,
   getXfaPageViewport,
   GlobalWorkerOptions,
   ImageKind,
@@ -101,6 +104,7 @@ export {
   ResponseException,
   setLayerDimensions,
   shadow,
+  SignatureExtractor,
   stopEvent,
   SupportedImageMimeTypes,
   TextLayer,

web/signature_manager.css

@@ -571,14 +571,23 @@
             user-select: none;
           }
 
-          #addSignatureSaveWarning {
+          &:not(.fullStorage) #addSignatureSaveWarning {
+            display: none;
+          }
+
+          &.fullStorage #addSignatureSaveWarning {
+            display: block;
+            opacity: 1;
             color: var(--save-warning-color);
             font-size: 11px;
           }
 
-          &[disabled] {
+          &:is([disabled], .fullStorage) {
             pointer-events: none;
-            opacity: 0.4;
+
+            > :not(#addSignatureSaveWarning) {
+              opacity: 0.4;
+            }
           }
         }
       }

web/signature_manager.js

@@ -16,6 +16,7 @@
 import {
   DOMSVGFactory,
   noContextMenu,
+  SignatureExtractor,
   stopEvent,
   SupportedImageMimeTypes,
 } from "pdfjs-lib";
@@ -81,6 +82,8 @@ class SignatureManager {
 
   #overlayManager;
 
+  #signatureStorage;
+
   #uiManager = null;
 
   static #l10nDescription = null;
@@ -111,7 +114,8 @@ class SignatureManager {
       saveContainer,
     },
     overlayManager,
-    l10n
+    l10n,
+    signatureStorage
   ) {
     this.#addButton = addButton;
     this.#clearButton = clearButton;
@@ -131,6 +135,7 @@ class SignatureManager {
     this.#saveContainer = saveContainer;
     this.#typeInput = typeInput;
     this.#l10n = l10n;
+    this.#signatureStorage = signatureStorage;
 
     SignatureManager.#l10nDescription ||= Object.freeze({
       signature: "pdfjs-editor-add-signature-description-default-when-drawing",
@@ -564,7 +569,7 @@ class SignatureManager {
       return;
     }
 
-    const outline = (this.#extractedSignatureData =
+    const { outline } = (this.#extractedSignatureData =
       this.#currentEditor.getFromImage(data.bitmap));
 
     if (!outline) {
@@ -617,6 +622,10 @@ class SignatureManager {
     this.#currentEditor = editor;
     this.#uiManager.removeEditListeners();
 
+    const isStorageFull = await this.#signatureStorage.isFull();
+    this.#saveContainer.classList.toggle("fullStorage", isStorageFull);
+    this.#saveCheckbox.checked = !isStorageFull;
+
     await this.#overlayManager.open(this.#dialog);
 
     const tabType = this.#tabButtons.get("type");
@@ -653,7 +662,7 @@ class SignatureManager {
     this.#tabsToAltText = null;
   }
 
-  #add() {
+  async #add() {
     let data;
     switch (this.#currentTab) {
       case "type":
@@ -667,12 +676,28 @@ class SignatureManager {
         break;
     }
     this.#currentEditor.addSignature(
-      data,
+      data.outline,
       /* heightInPage */ 40,
       this.#description.value
     );
     if (this.#saveCheckbox.checked) {
-      // TODO
+      const description = this.#description.value;
+      const { newCurves, areContours, thickness, width, height } = data;
+      const signatureData = await SignatureExtractor.compressSignature({
+        outlines: newCurves,
+        areContours,
+        thickness,
+        width,
+        height,
+      });
+      const uuid = (this.#currentEditor._signatureUUID =
+        await this.#signatureStorage.create({
+          description,
+          signatureData,
+        }));
+      if (!uuid) {
+        console.warn("SignatureManager.add: cannot save the signature.");
+      }
     }
     this.#finish();
   }

web/viewer.html

@@ -742,7 +742,7 @@ See https://github.com/adobe-type-tools/cmap-resources
                   <input type="checkbox" id="addSignatureSaveCheckbox" checked="true" tabindex="0"></input>
                   <label for="addSignatureSaveCheckbox" data-l10n-id="pdfjs-editor-add-signature-save-checkbox">Save signature</label>
                   <span></span>
-                  <span id="addSignatureSaveWarning" hidden="true" data-l10n-id="pdfjs-editor-add-signature-save-warning-message">You’ve reached the limit of 5 saved signatures. Remove one to save more.</span>
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