This does seem, at the least, irresponsible of the browser vendors. I'll be especially angry if Chrome doesn't have very prominent warnings, considering they harass some developers and power users with a warning about an "insecure" configuration Google basically forced them to use.[0] By analogy, I expect nothing less than a blinking red warning covering the entire browser window whenever keys are being logged because of an environment variable.

I also don't think readers should be encouraged so readily to put this into the persistent global environment.

[0] https://code.google.com/p/chromium/issues/detail?id=337734