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Environment
Description
Every network show as "perfectly received" / "very near", including networks that are far and show properly under Windows.
Under About this Mac->System Report->Wi-Fi, I can see all the networks around me and their Signal/Noise are all different.
-15 to -40 dBm / all 0 dBm except the connected network with -95dBm

RSSI is reported correctly when using itlwm 1.1.0 + Heliport 1.0.1, or itlwm 1.2.0 + Heliport 1.0.1.
Bug Report Archive
AirportItlwm.log
Kext Download Source
Github 1.1.0 stable release
I also had this bug once. Does not know what trigger it.
Same issue here.
Kext Version: AirportItlwm 1.1.0
WiFi Card Model: AC7260
macOS Version: 10.15.7
Wifi Explorer Lite is showing all weak (neighbour) networks as 100%. Best Networks are below. My connected network is 64% (Should be about 80%).
Fixed in b919444
Most helpful comment
Fixed in b919444