CSS counters behavior test cases:

nested-list

Firefox latest (82 or later)
1. 1. (1)
    2. 1. (1-1)
    3. 2. (1-2)
4. 2. (2)
    5. 1. (2-1)
    6. 2. (2-2)
1. 1. (1)
    2. 1-1. (1-1)
    3. 1-2. (1-2)
4. 2. (2)
    5. 2-1. (2-1)
    6. 2-2. (2-2)
1. 1. (1)
    1. 1. (1-1)
    2. 2. (1-2)
2. 3. (2)
    1. 1. (2-1)
    2. 2. (2-2)
1. 1. (1)
    1. 1. (1-1)
    2. 2. (1-2)
2. 3. (2)
    1. 1. (2-1)
    2. 2. (2-2)
Firefox 68
1. 1. (1)
    2. 1. (1-1)
    3. 2. (1-2)
4. 2. (2)
    5. 1. (2-1)
    6. 2. (2-2)
1. 1. (1)
    2. 1-1. (1-1)
    3. 1-2. (1-2)
4. 2. (2)
    5. 2-1. (2-1)
    6. 2-2. (2-2)
1. 1. (1)
    1. 1. (1-1)
    2. 2. (1-2)
2. 3. (2)
    1. 1. (2-1)
    2. 2. (2-2)
1. 1. (1)
    1. 1. (1-1)
    2. 2. (1-2)
2. 3. (2)
    1. 1. (2-1)
    2. 2. (2-2)
Firefox 67
1. 1. (1)
    1. 1. (1-1)
    2. 2. (1-2)
2. 2. (2)
    1. 1. (2-1)
    2. 2. (2-2)
1. 1. (1)
    1. 1-1. (1-1)
    2. 1-2. (1-2)
2. 2. (2)
    1. 2-1. (2-1)
    2. 2-2. (2-2)
1. 1. (1)
    1. 2. (1-1)
    2. 3. (1-2)
2. 4. (2)
    1. 5. (2-1)
    2. 6. (2-2)
1. 1. (1)
    1. 2. (1-1)
    2. 3. (1-2)
2. 4. (2)
    1. 5. (2-1)
    2. 6. (2-2)
Google Chrome
1. 1. (1)
    1. 1. (1-1)
    2. 2. (1-2)
2. 2. (2)
    1. 1. (2-1)
    2. 2. (2-2)
1. 1. (1)
    1. 1-1. (1-1)
    2. 1-2. (1-2)
2. 2. (2)
    1. 2-1. (2-1)
    2. 2-2. (2-2)
1. 1. (1)
    1. 1. (1-1)
    2. 2. (1-2)
2. 3. (2)
    1. 1. (2-1)
    2. 2. (2-2)
1. 1. (1)
    1. 1. (1-1)
    2. 2. (1-2)
2. 3. (2)
    1. 1. (2-1)
    2. 2. (2-2)

flat-headings

Firefox latest (82 or later)
1. (h1) 1
1-1. (h2) 1-1
1-2. (h2) 1-2
1-2-1. (h3) 1-2-1
2. (h1) 2
2-3. (h2) 2-1
2-4. (h2) 2-2
2-4-2. (h3) 2-2-1
1. (h1) 1
1-1. (h2) 1-1
1-2. (h2) 1-2
1-2-1. (h3) 1-2-1
2. (h1) 2
2-1. (h2) 2-1
2-2. (h2) 2-2
2-2-1. (h3) 2-2-1
Firefox 68
1. (h1) 1
1-1. (h2) 1-1
1-2. (h2) 1-2
1-2-1. (h3) 1-2-1
2. (h1) 2
2-1. (h2) 2-1
2-2. (h2) 2-2
2-2-1. (h3) 2-2-1
1. (h1) 1
1-1. (h2) 1-1
1-2. (h2) 1-2
1-2-1. (h3) 1-2-1
2. (h1) 2
2-1. (h2) 2-1
2-2. (h2) 2-2
2-2-1. (h3) 2-2-1
Firefox 67
1. (h1) 1
1-1. (h2) 1-1
1-2. (h2) 1-2
1-2-1. (h3) 1-2-1
2. (h1) 2
2-1. (h2) 2-1
2-2. (h2) 2-2
2-2-1. (h3) 2-2-1
1. (h1) 1
1-1. (h2) 1-1
1-2. (h2) 1-2
1-2-1. (h3) 1-2-1
2. (h1) 2
2-3. (h2) 2-1
2-4. (h2) 2-2
2-4-2. (h3) 2-2-1
Google Chrome
1. (h1) 1
1-1. (h2) 1-1
1-2. (h2) 1-2
1-2-1. (h3) 1-2-1
2. (h1) 2
2-1. (h2) 2-1
2-2. (h2) 2-2
2-2-1. (h3) 2-2-1
1. (h1) 1
1-1. (h2) 1-1
1-2. (h2) 1-2
1-2-1. (h3) 1-2-1
2. (h1) 2
2-1. (h2) 2-1
2-2. (h2) 2-2
2-2-1. (h3) 2-2-1

wrong-markup

Firefox latest (82 or later) [Firefox 82 - capture]
1. 1. (1)
2. 2. (2)
    3. 1. (2-1)
4. 3. (3?)
5. 4. (4?)
1. 1. (1)
2. 2. (2)
    3. 2-1. (2-1)
4. 3. (3?)
5. 4. (4?)
1. 1. (1)
2. 2. (2)
    1. 1. (2-1)
3. 2. (3?)
4. 3. (4?)
1. 1. (1)
2. 2. (2)
    1. 1. (2-1)
3. 2. (3?)
4. 3. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
2. 3. (3?)
3. 4. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
2. 3. (3?)
3. 4. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
3. 3. (3?)
4. 4. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
3. 3. (3?)
4. 4. (4?)
Firefox 68 [Firefox 68 - capture]
1. 1. (1)
2. 2. (2)
    3. 1. (2-1)
4. 2. (3?)
5. 3. (4?)
1. 1. (1)
2. 2. (2)
    3. 2-1. (2-1)
4. 2-2. (3?)
5. 2-3. (4?)
1. 1. (1)
2. 2. (2)
    1. 1. (2-1)
2. 2. (3?)
3. 3. (4?)
1. 1. (1)
2. 2. (2)
    1. 1. (2-1)
2. 2. (3?)
3. 3. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
2. 3. (3?)
3. 4. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
2. 3. (3?)
3. 4. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
2. 3. (3?)
3. 4. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
2. 3. (3?)
3. 4. (4?)
Firefox 67 [Firefox 67 - capture]
1. 1. (1)
2. 2. (2)
    1. 1. (2-1)
3. 2. (3?)
4. 3. (4?)
1. 1. (1)
2. 2. (2)
    1. 2-1. (2-1)
3. 2-2. (3?)
4. 2-3. (4?)
1. 1. (1)
2. 2. (2)
    1. 3. (2-1)
3. 4. (3?)
4. 5. (4?)
1. 1. (1)
2. 2. (2)
    1. 3. (2-1)
3. 4. (3?)
4. 5. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
3. 3. (3?)
4. 4. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
3. 3. (3?)
4. 4. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
3. 3. (3?)
4. 4. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
3. 3. (3?)
4. 4. (4?)
Google Chrome [Chrome - capture]
1. 1. (1)
2. 2. (2)
    1. 1. (2-1)
3. 2. (3?)
4. 3. (4?)
1. 1. (1)
2. 2. (2)
    1. 2-1. (2-1)
3. 2-2. (3?)
4. 2-3. (4?)
1. 1. (1)
2. 2. (2)
    1. 1. (2-1)
3. 2. (3?)
4. 3. (4?)
1. 1. (1)
2. 2. (2)
    1. 1. (2-1)
3. 2. (3?)
4. 3. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
3. 3. (3?)
4. 4. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
3. 3. (3?)
4. 4. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
3. 3. (3?)
4. 4. (4?)
1. 1. (1)
2. 2. (2)
    * (2-1)
3. 3. (3?)
4. 4. (4?)