CONSOLE MESSAGE: line 18: Blocked attempt to expand the option list to 20000 items. The maximum number of items allowed is 10000.
This test that setting HTMLSelectElement.length is capped to 10,000, but that you can add additional Option elements by calling add.

Select length is 0
Trying: - sel.length = 20000;
Select length is 0
Trying: - sel.add(new Option, 0);
Select length is 1
Trying: - sel.length = 0;
Select length is 0