Report preparation

• I used the AI-assisted bug report tool (Help → Support → File an Issue)
• I have attached a support bundle or log file

What happened?

What happened

The RX filter passband overlay on the panadapter — the shaded
region between the filter low and high edge markers — is nearly
invisible on macOS in v26.6.1.1. The filter edge lines are
visible but the fill between them has effectively no opacity,
making it impossible to see where the passband is at a glance.

Adjusting the panadapter background brightness (more or less
intense) does not help — the overlay remains imperceptible
regardless of background settings.

Screenshot

The screenshot shows the panadapter with a 3.0K LSB filter on
7.088 MHz. The filter edge markers are visible but the shaded
fill region between them is essentially invisible. Note that
the decorative background waves of the panadapter are more
visible than the filter passband overlay itself — which
illustrates the severity of the rendering issue.

Steps to reproduce

1. Launch AetherSDR v26.6.1.1 on macOS
2. Connect to FLEX-8600M
3. Open any slice in LSB or USB mode
4. Observe the RX filter passband overlay on the panadapter —
   the shaded region between the filter edge markers is
   nearly invisible

Expected: Shaded semi-transparent region clearly visible
between the filter edge markers, as it appears on Windows.

Actual: The region between the filter edges is nearly
transparent — the overlay is imperceptible against the
panadapter background regardless of background intensity
setting.

Platform comparison

Regression

This was working correctly in v26.5.x. The issue was introduced
in v26.6.1.1 on macOS. Windows is not affected, suggesting a
platform-specific rendering path difference — possibly related
to Metal vs OpenGL/Vulkan rendering, or an alpha compositing
difference in the Qt6 paint pipeline on macOS.

Environment

• AetherSDR: v26.6.1.1

• Hardware: Mac Studio M2 Max
• Radio: FLEX-8600M, firmware 4.2.18
• Callsign: WP4SK

What did you expect?

Shaded semi-transparent region clearly visible
between the filter edge markers, as it appears on Windows.

Steps to reproduce

Launch AetherSDR v26.6.1.1 on macOS
Connect to FLEX-8600M
Open any slice in LSB or USB mode
Observe the RX filter passband overlay on the panadapter —
the shaded region between the filter edge markers is
nearly invisible

AetherSDR version

26.6.1.1

Radio model & firmware

4.2.20

Operating system

macOS

OS version and hardware

macOS: Sequoia 15.7.5