Ordered list not incrementing when put directly after an unordered list

[Vringe]

Describe the bug
If you put an ordered list directly after an unordered list, the numbers are not incrementing.
As soon as you put an empty line between, the numbers are correct.

To Reproduce
Steps to reproduce the behavior:

1. Go to https://video.etherpad.com/
2. Create a new pad
3. Create an unordered list with 2 list items
4. Create an ordered list directly after

Expected behavior
An ordered list should increment its number

Screenshots

Server (please complete the following information):

• Etherpad version: 1.8.14
• OS: Host runs Ubuntu 18.04 (But I'm using the official docker image)
• Node.js version (node --version): v14.17.1
• npm version (npm --version): 6.14.13

Desktop (please complete the following information):

• OS: Mac OS 11.4
• Browser Chrome & Firefox
• Version 92.0.4515.159 (Chrome) & 91 (Firefox)

[webzwo0i]

Thank you!

As a side note: importing HTML that was exported from a pad which is in a state as described above (ie all list numbers are "1") will also result in false list numbers. So I assume the bug is in contentcollector.js

[JohnMcLear]

Confirmed. Will work on this ASAP :)

[JohnMcLear]

Test coverage is available, I intend to work on a fix once we have some bad weather and I'm stuck inside.

[rhansen]

Possibly related to #5176.