How To Hide Priority Icon In Agile Board
Description
You would like to remove the priority icon/indicator from boards.
Workaround
Please note "Priority" is a System Field and is required.
At this time, there is no out-of-the-box option to hide issues priorities in Jira, these steps will outline the available workaround at this time, which is hiding the Priority field.
This covers hiding existing issues with priorities set as well as hiding future issues if you set them to the new Priority.
Create a new Priority by going to https://<instance-url>/secure/admin/ViewPriorities.jspa
You can name this new priority "None", assign it the color white (#ffffff), and for the image URL, you can use a transparent gif.
You can save the transparent image below (placed within the border) and upload it to your server. You may also use a data URL to set the image.
After you do that, bulk edit issues and set the Priority field to "None" for your selected issues.
By doing this, no icon will appear on your board.
Then set the Priority field back to no show in field configuration, and no icons should show for future issues as well since the Priority field cannot be set.