Rearrange or Hide Issue Fields
You can change the order in which fields are displayed for everyone on an issue page. Bring the field you consider the most important to the top, leaving rarely used fields at the bottom.
You can also hide any custom field and certain default fields.
On the Issues page, click the Settings button:
In the Issue fields tab:
Drag fields up or down the list to change their order.
Click the toggles to hide/unhide fields.