RDM 2026.2.1.2 (macOS): RDP-via-RD-Gateway always fails — network monitor loops "Network transition detected - Pausing connections"

Environment

• Remote Desktop Manager 2026.2.1.2 (64-bit), macOS (Apple Silicon)
• Embedded RDP engine: …/Remote Desktop Manager.app/Contents/MonoBundle/libDevolutionsRdp.dylib
• Connection type: RDP (Microsoft Remote Desktop) through an RD Gateway (WebSocket-based, open-source rdpgw)
• Gateway server: stage-rdpgw.oneclick.services:443 (valid Let's Encrypt cert, reachable, /remoteDesktopGateway/ returns HTTP 401 as expected)
• Connection Host: a per-session hostname (e.g. u3wsva2djj-stage.oneclick.services) that is only resolvable through the gateway, not via local/public DNS (by design — the gateway resolves it internally)

Problem Every connection attempt fails within ~3 seconds with:
ERROR Could not establish a secure connection to the host (0x00020008)
(occasionally Connection failed (0x00020006)). Nothing ever reaches the gateway server (verified server-side: no handshake/auth is logged).

Root cause (from RDM debug+verbose log) RemoteDesktopManager.debug shows, in the same second as the error:
DEBUG Network monitoring initialized for host: u3wsva2djj-stage.oneclick.services
DEBUG Network transition detected for host: u3wsva2djj-stage.oneclick.services - Pausing connections
DEBUG Certificate verification skipped: Network transition in progress
→ ERROR Could not establish a secure connection to the host (0x00020008)
The network monitor then loops endlessly, emitting dozens of identical lines per second and never settling:
DEBUG Network restored for host: … - Starting stabilization period
DEBUG Network transition detected for host: … - Pausing connections
It appears the network monitor performs a reachability check tied to the connection's Host, and because that Host is only resolvable via the gateway (not local DNS), the check fails permanently → it perpetually reports a "network transition" and pauses the connection, so the actual connect never proceeds (TLS/cert verification is explicitly skipped).

Proof this is RDM-specific (not network/gateway/target)

• The native Microsoft RDP client (Windows App / mstsc) connects successfully to the same gateway + same Host from the same Mac and network.
• A FreeRDP 3.x-based client also connects successfully to the same gateway.
• Gateway endpoint reachable from the Mac (TCP/TLS OK via openssl/nc); macOS Application Firewall is disabled; no Little Snitch / network-filter extensions.
• This connection worked previously (January 2026) on an older RDM version (which used the separate FreeRDPSandboxed.app engine and did not have this network-monitoring behavior). On 2026.2.x no SessionLogs/*.log is written for these attempts — the engine aborts before a session starts.
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Already tried (no effect)

• Clean reinstall of RDM 2026.2.1.2
• Recreating the connection entry from scratch
• Gateway Transport = Auto and = HTTP
• Stopping Tailscale/VPN (the monitor kept flapping for 90s+ afterwards)
• No user-facing toggle for this in RemoteDesktopManager.cfg
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Questions / request

1. How can the RDP network-monitoring / "network transition" pausing behavior be disabled?
2. This looks like a false-positive when the RDP Host is only resolvable through the RD Gateway (common with gateway-brokered/per-session hostnames). Can the monitor be fixed to not block such connections (e.g. check the gateway reachability instead of the inner Host)?