FIX for issue#14855 According to MySQL fulltext documentation, AGAINST values shoud be stripped of special chars if they are not intended to be used https://dev.mysql.com/doc/refman/5.5/en/fulltext-search.html Searching "*" in any grid list causes a 400 error because of no filtering is applied.

Author: phoenix128

lib/internal/Magento/Framework/View/Element/UiComponent/DataProvider/FulltextFilter.php

@@ -62,6 +62,16 @@ function ($column) use ($alias) {
         return $columns;
     }
 
+    /**
+     * Escape against value
+     * @param string $value
+     * @return string
+     */
+    private function escapeAgainstValue(string $value): string
+    {
+        return preg_replace('/([+\-><\(\)~*\"@]+)/', ' ', $value);
+    }
+
     /**
      * Apply fulltext filters
      *
@@ -86,7 +96,7 @@ public function apply(Collection $collection, Filter $filter)
         $collection->getSelect()
             ->where(
                 'MATCH(' . implode(',', $columns) . ') AGAINST(?)',
-                $filter->getValue()
+                $this->escapeAgainstValue($filter->getValue())
             );
     }
 }