diff --git a/__mocks__/imageMock.ts b/__mocks__/assetMock.ts
similarity index 67%
rename from __mocks__/imageMock.ts
rename to __mocks__/assetMock.ts
index 69e664597f..5412bc08dc 100644
--- a/__mocks__/imageMock.ts
+++ b/__mocks__/assetMock.ts
@@ -3,4 +3,4 @@
  * Licensed under MIT License. See LICENSE in root directory for more information.
  */
 
-export default {};
+export default ""; // mostly path to bundled file or data-url (webpack)
diff --git a/package.json b/package.json
index 76deb82028..1c32eaa61f 100644
--- a/package.json
+++ b/package.json
@@ -62,7 +62,7 @@
     },
     "moduleNameMapper": {
       "\\.(css|scss)$": "<rootDir>/__mocks__/styleMock.ts",
-      "\\.(svg)$": "<rootDir>/__mocks__/imageMock.ts"
+      "\\.(svg|png|jpg|eot|woff2?|ttf)$": "<rootDir>/__mocks__/assetMock.ts"
     },
     "modulePathIgnorePatterns": [
       "<rootDir>/dist",
diff --git a/src/renderer/components/icon/icon.tsx b/src/renderer/components/icon/icon.tsx
index d61d57c663..1335f344ad 100644
--- a/src/renderer/components/icon/icon.tsx
+++ b/src/renderer/components/icon/icon.tsx
@@ -37,7 +37,7 @@ export class Icon extends React.PureComponent<IconProps> {
     focusable: true,
   };
 
-  static isSvg(content: string){
+  static isSvg(content: string) {
     return String(content).includes("svg+xml"); // data-url for raw svg-icon
   }
 
@@ -63,7 +63,7 @@ export class Icon extends React.PureComponent<IconProps> {
     switch (evt.nativeEvent.code) {
       case "Space":
 
-        // fallthrough
+      // fallthrough
       case "Enter": {
         this.ref.current?.click();
         evt.preventDefault();
@@ -104,10 +104,11 @@ export class Icon extends React.PureComponent<IconProps> {
     // render as inline svg-icon
     if (typeof svg === "string") {
       const dataUrlPrefix = "data:image/svg+xml;base64,";
-      const svgIconDataUrl: string = svg.startsWith(dataUrlPrefix) ? svg : require(`./${svg}.svg`);
-      const svgIconText = decode(svgIconDataUrl.replace(dataUrlPrefix, "")); // get raw xml
+      const svgIconDataUrl = svg.startsWith(dataUrlPrefix) ? svg : require(`./${svg}.svg`);
+      const svgIconText = typeof svgIconDataUrl == "string" // decode xml from data-url
+        ? decode(svgIconDataUrl.replace(dataUrlPrefix, "")) : "";
 
-      iconContent = <span className="icon" dangerouslySetInnerHTML={{ __html: svgIconText }}/>;
+      iconContent = <span className="icon" dangerouslySetInnerHTML={{ __html: svgIconText }} />;
     }
 
     // render as material-icon
@@ -135,7 +136,7 @@ export class Icon extends React.PureComponent<IconProps> {
     }
 
     if (href) {
-      return <a {...iconProps} href={href} ref={this.ref}/>;
+      return <a {...iconProps} href={href} ref={this.ref} />;
     }
 
     return <i {...iconProps} ref={this.ref} />;
diff --git a/types/mocks.d.ts b/types/mocks.d.ts
index cc260eacfd..0fbde3b4f9 100644
--- a/types/mocks.d.ts
+++ b/types/mocks.d.ts
@@ -27,6 +27,7 @@ declare module "*.scss" {
 }
 
 // Declare everything what's bundled as webpack's type="asset/resource"
+// Should be mocked for tests support in jestConfig.moduleNameMapper (currently in "/package.json")
 declare module "*.svg";
 declare module "*.jpg";
 declare module "*.png";