UI latency and slow connection handling on CachyOS / KDE Plasma 6 (Avalonia UI)

Hi Devolutions Team,
I am experiencing severe performance issues with RDM on CachyOS (Arch-based, KDE Plasma 6 / Wayland & X11). The issue persists on both native (AUR) and Flatpak versions, as well as with a purely local XML/SQLite data source (Connections.db).
Symptoms:

• Extreme UI lag: Simple actions like closing a tab, clicking nodes, or opening settings take 5–6 seconds to respond.
• Double-clicking an entry has a long delay before connection starts.
• Modifying UI settings, scaling, or disabling H.264 codecs did not resolve the UI thread bottleneck.

System Info:

• OS: CachyOS (Linux kernel with BORE/EEVDF scheduler)
• Desktop Environment: KDE Plasma 6 (Wayland / XWayland)
• RDM Version: [Deine RDM Version eintragen]

Console Log Output:
Below is the output when running RDM via terminal. Noticeably, FreeRDP reports experimental build options with WITH_VERBOSE_WINPR_ASSERT=ON and fails on the H.264 codec context:

flatpak run com.devolutions.remotedesktopmanager
Gtk-Message: 11:40:10.835: Failed to load module "xapp-gtk3-module"
Gtk-Message: 11:40:10.835: Failed to load module "canberra-gtk-module"
[11:40:44:370] [2:00000402] [INFO][Devolutions.Rdp.Credentials] - [Parse]: parsing "s*****", "a****.c*" (Mstsc) => "Username: "s*****" Domain: "a****.c*""
[11:40:44:374] [2:00000402] [INFO][com.freerdp.codec] - [openh264_init]: Using OpenH264 library path from environment: /usr/lib/libopenh264.so
[11:40:44:374] [2:00000402] [WARN][com.freerdp.core.codecs] - [freerdp_client_codecs_prepare]: Failed to create h264 codec context
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x7f6f8000a150]: *************************************************
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x7f6f8000a150]: This build is using [experimental] build options:
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x7f6f8000a150]: * 'WITH_MBEDTLS=ON'
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x7f6f8000a150]: *
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x7f6f8000a150]: [experimental] build options might crash the application
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x7f6f8000a150]: *************************************************
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x7f6f8000a150]: *************************************************
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x7f6f8000a150]: This build is using [runtime-check] build options:
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x7f6f8000a150]: * 'WITH_VERBOSE_WINPR_ASSERT=ON'
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x7f6f8000a150]: *
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x7f6f8000a150]: [runtime-check] build options might slow down the application
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x7f6f8000a150]: *************************************************
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn_cipher][0x7f6f8000a150]: *************************************************
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn_cipher][0x7f6f8000a150]: [SSL] {Cipher} build or configuration missing:
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn_cipher][0x7f6f8000a150]: * des-ede3-cbc: RDP security will not work
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.rdp] - [log_build_warn_cipher][0x7f6f8000a150]: *************************************************
[11:40:44:377] [2:00000402] [WARN][com.freerdp.core.nego] - [nego_enable_aad]: This build does not support AAD security, disabling.
[11:40:44:713] [2:00000402] [INFO][com.freerdp.core.auth] - [auth_resolve_sspi_table]: Using SSPI Module: /app/lib/devolutions/RemoteDesktopManager/libDevolutionsSspi.so
[11:40:45:951] [2:00000402] [INFO][com.freerdp.gdi] - [gdi_init_ex]: Local framebuffer format  PIXEL_FORMAT_BGRX32
[11:40:45:951] [2:00000402] [INFO][com.freerdp.gdi] - [gdi_init_ex]: Remote framebuffer format PIXEL_FORMAT_BGRA32
[11:40:45:953] [2:00000402] [INFO][com.freerdp.channels.rdpsnd.client] - [rdpsnd_load_device_plugin]: [static] Loaded alsa backend for rdpsnd
[11:40:45:963] [2:00000402] [INFO][com.freerdp.channels.drdynvc.client] - [dvcman_load_addin]: Loading Dynamic Virtual Channel nowproto
[11:40:45:963] [2:00000402] [INFO][com.freerdp.channels.drdynvc.client] - [dvcman_load_addin]: Loading Dynamic Virtual Channel ainput
[11:40:45:963] [2:00000402] [INFO][com.freerdp.channels.drdynvc.client] - [dvcman_load_addin]: Loading Dynamic Virtual Channel rdpsnd
[11:40:45:963] [2:00000402] [INFO][com.freerdp.channels.drdynvc.client] - [dvcman_load_addin]: Loading Dynamic Virtual Channel rdpgfx
[11:40:45:963] [2:00000402] [INFO][com.freerdp.channels.drdynvc.client] - [dvcman_load_addin]: Loading Dynamic Virtual Channel disp
[11:40:45:964] [2:00000402] [WARN][com.winpr.thread] - [SetThreadPriority]: pthread_setschedprio(0) not implemented, requires POSIX 2008 or later
[11:40:46:004] [2:0000041c] [WARN][com.freerdp.core.codecs] - [freerdp_client_codecs_prepare]: Failed to create h264 codec context
[11:40:46:213] [2:0000041d] [INFO][com.freerdp.client.common] - [client_common_save_session_info]: Logon Info V2 [AKROS\schmda [2]]
[11:40:46:213] [2:0000041d] [INFO][com.freerdp.client.common] - [client_common_save_session_info]: Logon Extended Info [cookie: TRUE, LogonId: 2, errorInfo: FALSE, notifyType: 0, notifyData: 0]
[11:40:46:309] [2:0000041c] [INFO][com.freerdp.channels.rdpsnd.client] - [rdpsnd_load_device_plugin]: [dynamic] Loaded alsa backend for rdpsnd

Thanks
David