Edit the file: libraries/joomla/html/html.php
Go to the line ~879 and find this line:
'window.addEvent(\'domready\', function() {Calendar.setup({
And replace it with this line:
'window.addEvent(\'load\', function() {Calendar.setup({
Save the file and test.
Billing and invoicing are at the core of any business as it forms a mechanism to receive payments for the services rendered or the products offered. It is no longer perceived as ‘yet another’ activity in the routine business cycle, but instead has been recognized as an integral and important business process.
Why my Joomla website performance is bad?