Help: Trailing slash disappeared?

I am setting up my new site

It was using trailing slashes, but I just now noted that it is no longer doing so.

For example:

It was: https://www.example.com/contact/

It is now: https://www.example.com/contact

I want the trailing slash.

I did edited .htaccess to rewrite naked requests to www versions. Thinking that may have caused it, I commented those 2 lines out - refreshed page, cleared the cache, refreshed page again - but still no trailing slash.

I have done various other things, but mainly within admin - except for a blueprint file to add metadata field to the content tab under the ttitle.

Any ideas what I may have done wrong?