First of all, we already agreed that changing NAV or TOC should NOT affect what’s in the actual text, which is just how it works now, both in Sigil and Calibre.
So let’s see how entries moves in Sigil.
First of all, I created a file that contains 8 h1 tags.
And the TOC looks like this:
Lets move B to the right (indent it).
No problem, and continue clicking Right does nothing. That means the level must be continuous.
Then move C to right once, it becomes sub-level of A, Twice and it becomes sub-level of B.
Lets move D to the farest right for the next setp.
Now, move C to the left,
We can see D moved with C, it’s parent-level, as a whole.
Let’s say we have a configuration like this:
And move C to left:
So D and E moved with C.
And move C to right again:
We can see D/E/F/G all moved with C. Because we make C be the parent-level to all of these.
You can also make it past 6 levels
As to move up or down, it can only happens between entries with the same level, so not important.