Hi @Kena Mistry,The <style> you added in SPD doesn't work on SharePoint modern page, It will only work on classic page. As per my understanding, currently you cannot format SharePoint default Title column. You could only use the following customRowAction
available & supported in JSON formatting.
Documentation: SharePoint JSON Formatting - customRowAction
As a workaround, you could manually increase the width of column header by dragging it to the right & save the library view.
Since it turns out to be a by-design one. And I noticed that some end users have also proposed the same request. It is highly recommended that you could raise a ticket on feedback. And I will vote up the ticket for you. Many features of our current products are designed and upgraded based on customers’ feedback. Thanks for your understanding.
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