I am using 5.6.3.4 and using Designer Content to create blocks. I have customised the blocks by adding tabs. Other than that, it's pretty straightforward and everything is functioning well.
My problem is when I try to add and save a new block the first time, it keeps showing me the 'loading' icon but does not save the block. If I refresh the page and try adding the block again, it works. Sometimes it happens randomly and when I refresh the page and save, it works. Is there anything that's causing this and how can I fix this?
I have all cache turned off and am trying this on my localhost. The site does not have any other add-ons installed other than Designer Content. The site is using Bootstrap.