upgrade fullcalendar.js to version 3.10.5
upgrade moment.js to version 2.20.1
I am using this plugin for a local calendar without davcal sync, so I have not tested the davcal functions. The local calendar suffered some display issues and a bug when selecting days in the monhtly calendar, which I fixed by upgrading the javascript libraries. Note that latest fullcalendar.js version 5.10+ would require substantial code rewrite as it dropped dependencies to jquery and moment.js. Download fullcalendar-3.10.5.zip, copy it to the davcal plugin folder, and change the references at the beginning of file script.js. Written by thalueng, 30 Jan 2022.
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