Hi @Vanessa ,
I tested it against the JSON code you provided, but it didn't quite work for me, my "Document11111111111......" filename has no wrap.
As we can easily drag the length of the column, automatic line wrapping is canceled by default in SharePoint Online. You can use the column JSON format to allow the file name to wrap. But this only applies to Title(in Lists). Filename (in Document Libraries) is currently not supported. That's probably why your retain single click doesn't work!
Please refer to this article:https://learn.microsoft.com/en-us/sharepoint/dev/declarative-customization/column-formatting#supported-column-types
I recommend you give suggestion in the feedback portal and help to make improvements. Many features of current products are designed and upgraded based on customers’ feedback. With requirements like this increase, the problem may well be released in the future. I will vote for you.
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