With the devel module activated (and 'Display page timer' on) the autocomplete on admin/config/blazemeter/blazemeter-config gives errors.
Related to: #128316: Devel causing problems with Ajax calls
This patch helped me.
Fixed in latest dev for both 6.x and 7.x branches.
Automatically closed -- issue fixed for 2 weeks with no activity.
This issue has no child issues.
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