Thanks for your comments. We could all complain, but I doubt that would do much good. For now, I'd like to adapt, and see how that goes. The plan:
1. Add links to the previously pinned messages to the welcome page.
2. To simulate edits, create a new post, then delete the old.
I only ever edit posts soon after creating them, so this looks feasible.
Alternatively, post corrections in responses.
3. Learn to live without syntax coloring. It will encourage me to be brief :-)
Alternatively, post a link to a comment in a Leo issue that does color properly.
Before getting all upset, I'm going to give the new look a try for a week or so. If that doesn't work, we can all consider alternatives.
Edward