Can I change the attachment size limit in ticket comments?
It is not possible to increase the attachment size limits.
If you want to send files that exceed these limits, use another method. You can choose to host those files on another site and send the customer the hyperlink to the file, or, on the Team plan and above, you can look into using a file-sharing app from our Marketplace, such as the Box app which allows you to share larger files.
For more information on attachments in tickets, see the article: Adding attachments to ticket comments.
For other related information, see this article: How many files can customers attach to a ticket through the web form?