Fixed issue boards not filtering when URL params are encoded

Closes #32084

app/assets/javascripts/lib/utils/common_utils.js

@@ -135,7 +135,7 @@
     gl.utils.getUrlParamsArray = function () {
       // We can trust that each param has one & since values containing & will be encoded
       // Remove the first character of search as it is always ?
-      return window.location.search.slice(1).split('&');
+      return window.location.search.slice(1).split('&').map(param => decodeURI(param));
     };
 
     gl.utils.isMetaKey = function(e) {

spec/javascripts/lib/utils/common_utils_spec.js

@@ -41,6 +41,16 @@ require('~/lib/utils/common_utils');
         const paramsArray = gl.utils.getUrlParamsArray();
         expect(paramsArray[0][0] !== '?').toBe(true);
       });
+
+      it('should decode params', () => {
+        history.pushState('', '', '?label_name%5B%5D=test');
+
+        expect(
+          gl.utils.getUrlParamsArray()[0],
+        ).toBe('label_name[]=test');
+
+        history.pushState('', '', '?');
+      });
     });
 
     describe('gl.utils.handleLocationHash', () => {