The only way to do this is to change the sizes in the html while editing. Therefore you need a browser which have development tools. And you need HTML knowhow to change it.
But this you would have to do manually every time you edit a roadmap.
I don't know any other solution...
For JSM June Challenge #2, share how your non-technical teams like HR, legal, marketing, finance, and beyond started using Jira Service Management! Tell us: Did they ask to start using it or...
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