Fix link paste detection concatenating URLs. Fix #12393

client/src/components/Draftail/decorators/Link.js

@@ -70,6 +70,12 @@ export const getValidLinkURL = (text, schemes) => {
     }
   }
 
+  // If there is whitespace, treat text as not a URL.
+  // Prevents scenarios like `URL.parse('https://test.t/ http://a.b/')`.
+  if (/\s/.test(text)) {
+    return false;
+  }
+
   try {
     const url = new URL(text);
 

client/src/components/Draftail/decorators/Link.test.js

@@ -118,6 +118,7 @@ describe.each`
   ${'http://test.example.co.uk'} | ${'http://test.example.co.uk'}
   ${'https://example.com'}       | ${'https://example.com'}
   ${'https://xn--ls8h.la'}       | ${'https://xn--ls8h.la'}
+  ${'http://sp.a http://c.e'}    | ${false}
   ${'ftp://example.com'}         | ${'ftp://example.com'}
   ${'ftps://example.com'}        | ${'ftps://example.com'}
   ${'//example.com'}             | ${false}