I know it's not exactly what you want, but I use Apache Guacamole to connect/switch between my VMs running on Proxmox, mostly Windows RDP, but also several SSH and VNC. it supports full screen and is fairly responsive for daily admin tasks.
This may not be exactly what you want, but I use Apache guacamole for this. The client becomes a web browser, and a chromium based browser allows seamless bidirectional clipboard. I use Ubuntu VMs with Mate as the DM and with a few keybinds tweaked it is solid. I use tightVNC as my server which supports dynamic resize, and the soon to be released guacamole 1.6 supports sending dynamic resize (since the underlying libraries are now updated to support it; RDP in guac already supports dynamic resize). How performant is it? I have a single proxmox vm which runs 3 Minecraft instances for our server's 3 bot accounts (which just stand still) and the desktop is still navigable.
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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