This isnt just a performance issue, this is a security issue.
Due to this addon Firefox on Ubuntu cannot utilize web content
sandboxing (which obviously depends on e10s) which means Ubuntu users
are being left vulnerable to security issues.
You received this bug notification because you are a member of Desktop
Packages, which is subscribed to ubufox in Ubuntu.
Please enable e10s (multi-core CPU processing) support
Status in Ubufox Extension:
Status in Ubuntu:
Status in ubufox package in Ubuntu:
Would it be possible to determine whether this add-on is compatible
with the e10s "electrolysis" feature of Firefox?
If it is, the manifest should say so: 
This link may help when determining support: 
Compatibility of this addon with e10s is required to enable the e10s
feature, which brings many speedups and enhancements, on default
configured ubuntu installations.
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