I am reading a book and simultaneously highlighting with the PDF viewer. I nest my blocks under headings and subheadings. But when the page becomes long with many headings, it is easy to get the indentations and heading levels (number of # ) out of kilter, which means that the ToC (I use the TOC Generator plug-in) gets confused and leaves headings out. To correct that, I keep having to count the indentation levels and the heading hashes to make sure they match.
@cannibalox came up with 2 suggestions. If you read through that thread you’ll notice I initially went for suggestion 2, but eventually settled for no.1 after cannibalox pointed out the drawback.
Bear in mind that since # Heading 1 is reserved for the page title, the highest level heading in your notes on any page will be # Heading 2. That means the 1st vertical line relates to # Heading 2, which aggravated me getting my knickers in a twist.
I have posted this here as it may be of use to others. If this is the wrong forum channel, please Ms/Mr moderator, move it to the right one.
A big shout-out to @cannibalox for his help!!! Thank you 