False positives on low-zoom and/or high-pixel-ratio

[steevee]

Steps to replicate

1. Go to https://fuckadblock.sitexw.fr/blockadblock/ without an adblocker enabled on Chrome (v70+)
2. Ensure browser zoom level is 100% and note value of window.devicePixelRatio
3. If window.devicePixelRatio == 1 then zoom out to 33% and refresh page.
   • Outcome: AdBlocker detected
   • Desired: AdBlocker should not be detected
   • N.b. If window.devicePixelRatio > 1 (i.e. testing on a retina screen) zoom level and window dimensions may differ slightly to above.

Technical issue

The above steps mean this._var.bait.offsetHeight, this._var.bait.offsetWidth, this._var.bait.clientHeight, this._var.bait.clientWidth all equal zero and flag detected.