Improve reliability of "show_file_choosers()"

Author: mdmintz

seleniumbase/fixtures/base_case.py

@@ -5423,6 +5423,12 @@ def ad_block(self):
     def show_file_choosers(self):
         """Display hidden file-chooser input fields on sites if present."""
         css_selector = 'input[type="file"]'
+        try:
+            self.wait_for_element_present(
+                css_selector, timeout=settings.MINI_TIMEOUT
+            )
+        except Exception:
+            pass
         try:
             self.show_elements(css_selector)
         except Exception: