Paste from Office should not break the list on the following blocks in the same list item or deduce a start attribute for a split list

[niegowski]

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Fix (paste-from-office): Paste from Office should not break the list on the following blocks in the same list item or deduce a start attribute for a split list. Closes #11210, closes #15964.

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[Witoso]

Self-reminder to put it into the comparison table. cc: @gorzelinski @godai78

[pszczesniak]

This solution covers most of mention cases, but i have found one case when it does not.

Here is the file: broken-list.docx

Please take a look at the indentation level, first one is "flattened" (as a proper list should look like - without omit the levels of lists).

CKE4 covers that case.

[Witoso]

@pszczesniak  we don't have support in CKE5 for so called "skip-level" lists, so the behavior is correct :)

[pszczesniak]

@Witoso thank you for clearing that up.