update codemirror plugin files

plugins/codemirror/codemirror.css

@@ -19,7 +19,7 @@
 }
 
 .CodeMirror-scrollbar-filler, .CodeMirror-gutter-filler {
-  background-color: transparent; /* The little square between H and V scrollbars */
+  background-color: white; /* The little square between H and V scrollbars */
 }
 
 /* GUTTER */

plugins/codemirror/codemirror.js

@@ -9793,7 +9793,7 @@
 
   addLegacyProps(CodeMirror);
 
-  CodeMirror.version = "5.59.3";
+  CodeMirror.version = "5.59.4";
 
   return CodeMirror;