the problem is probably that the tokens used in the form are no longer valid. You need to create a script which captures the tokens (http://learn.elgg.org/en/stable/guides/actions.html#security) and submit these in the form. view reply

for some more information about how to manipulate menus see http://learn.elgg.org/en/stable/guides/menus.html view reply

I have included community.elgg.org in our Let's Encrypt certificate and the issue should now be solved view reply

@Anshul, have you read the link Matt provided ( http://learn.elgg.org/en/stable/admin/duplicate-installation.html#database-entries) as that article covers everything you need to know when moving/duplicating your Elgg installation. This... view reply

icon handling is done in this view, check it out https://github.com/Elgg/Elgg/blob/2.3/views/default/output/icon.php If you wish to completely disable Fontawesome do as RvR suggested view reply

Bugfix release 1.12.16 and 2.3.3 is now available for download

don't include /engine/lib/ files. Maybe first have a look at http://learn.elgg.org/en/stable/tutorials/index.html view reply

or use Translation Editor to change it on the fly view reply