Accept button greyed out when trying to update VCSA

Background

Updating to new minor versions of VCSA is really simple since all the update functionality is built into the web interface living on port 5480 of the vCenter Server, also known as VAMI (vCenter Appliance Management Interface).

Problem

When trying to upgrade from 6.5.0.10000 Build Number 5973321 to 6.5.0.10100 Build Number 6671409 I wasn't able to click the Accept button because it was greyed out. Clicking the EULA link several times was of no help.

Solution

Switching browser helped. I originally tried using Chrome version 61.0.3163.100. Switching to Firefox version 56 revealed the Accept button and I could proceed with the update..