Priority values are displayed as small icons, have a look at the attached screenshot.
I don't see any need to change the width.

Did you see the screenshot I attached? No icons are visible. If this is not because the field is too narrow, please explain what else might be wrong

There is no icon displayed if priority is set to "none".

Priority is not set to none. Any other ideas please

ginganinga,

I was not able to reproduce your problem with a fresh install of the latest stable MantisBT release (1.2.19 at the moment).

If you are running an older version, I recommend that you upgrade to the latest (download from [1]). If after doing so the problem persists, do not hesitate to reopen the issue and provide detailed step-by-step instructions to reproduce the issue; the following additional information may also be useful:

• Exact version of MantisBT, PHP, Database, Web server, Browser and Operating System
• Relevant customizations (e.g. changes in config_inc.php, etc)
• Installed plugins or custom functions ?
• Was the MantisBT source code modified in any way ?

[1] http://mantisbt.org/download.php

FYI, it turns out that we customised priorities and missed associating the icons:

https://www.mantisbt.org/forums/viewtopic.php?t=5947&f=4

This bit was missed:

Customize icon associative arrays

$g_status_icon_arr = array (
LOW => 'prority_low_1.gif',
NORMAL => 'priority_1.gif',
HIGH => 'priority_2.gif',
URGENT => 'priority_3.gif');

Thanks for coming back and telling the solution.