By default FF integrates whatever A/V solution has been implemented on the host into each and every browsing session. That notwithstanding, per the wizards at Comodo:
IceDragon features privacy and performance enhancements over the Firefox core browser as well as additional features such as SiteInspector malware scanning, Comodo Secure DNS and improved social media functionality.
From this I infer that any host that has full proactive security configuration of the latest Comodo Internet Security Suite configured in full off-meds raving paranoid nutter mode HIPS Defense + / custom policy firewall policy will garner the best protection offset by the least performance hit.
SEE: Endpoint Detection and Response, Free - What is EDR Security?
I have no idea whether Ice Dragon is intrinsicly more secure independent of any A/V - compared to FF vanilla - but thing I’d be willing to stake all of your lives that CID + CIS will be. And, at the very least, such implementation will be more efficient than either CID with any other security product or CIS with any other browser.
If one is already implementing Comdodo Internet Security Suite in some configuration, then implementing CID as default browser can only enhance one’s internet security with NO performance hit. Whether CID v38 is optimal performing when implemented with CIS v5.12 is unknown to me. But I’m fairly confident it can’t hurt security even if performance is degraded.
Whatever functionality may be lost in CID v38 - in contrast to CID v26 - that’s the price that has to be paid to fix whatever bugs of intrinsic security nature may exist in FF v26 and so as to take full advantage of full integration with the latest version of CIS.
What? Bugs in FireFox? What? :o
posted from FireFox 38.0.6 - CID v26 fully patched add-on / extension / plug-in FEBE v8.3.1 exported profile - fully patched to most current add-on / extension / plug-in.