For detecting mobile devices we are using WURFL technology, and actually the latest NPM does not contain new definition
for Firefox v4 (because we don´t want to support beta version and because it´s problematic to support it).
But we have small workarround which solve you and yours customer problem:
1.Just open page
(via click on button "use this browser's user agent")
2.copy whole format of user agent from detected field
3. Add to users web_browsers_patch.xml in drive_letter\Inetpub\Solarwinds\bin directory code mentioned bellow with replaced browser agent and replaced name for his browser and version
<device user_agent="detected_browser_agent" fall_back="browser_name" id="browser_name_version_number">
<group id="product_info"><capability name="model_name" value="version_number" /></group></device>
For example for Firefox v4 RC1:
<device user_agent="Mozilla/5.0 (rv:2.0) Gecko/20100101 Firefox/4.0" fall_back="firefox" id="firefox_4_0">
<capability name="model_name" value="4.0" /></group>
According these steps you can "support" some none-supported browser like Fenec or Maxthon,etc(just if you want to optimize it for mobile preview).