docs: add rclone OS requirements

Adds rclone OS requirements list and latest rclone versions known to be working with specific historical OS versions.

Discussed on the forum:
https://forum.rclone.org/t/rclone-1-65-1-runtime-exception-error-crash-immediately-after-running-the-command/44051

Fixes: #7571

docs/content/downloads.md

@@ -10,6 +10,17 @@ Rclone is single executable (`rclone`, or `rclone.exe` on Windows) that you can
 simply download as a zip archive and extract into a location of your choosing.
 See the [install](https://rclone.org/install/) documentation for more details.
 
+## Release {{% version %}} OS requirements {#osrequirements}
+
+| OS | Minimum Version | 
+|:-------:|:-------:|
+| Linux | kernel 2.6.32 |
+| macOS (Intel) | 10.15 (Catalina) |
+| macOS (ARM64) | 11 (Big Sur) |
+| Windows | 10, Server 2016 |
+| FreeBSD | 12.2 |
+| OpenBSD | 6.9 |
+
 ## Release {{% version %}} {#release}
 
 | Arch-OS | Windows | macOS | Linux | .deb | .rpm | FreeBSD | NetBSD | OpenBSD | Plan9 | Solaris |
@@ -101,3 +112,19 @@ script) from a URL which doesn't change then you can use these links.
 ## Older Downloads
 
 Older downloads can be found [here](https://downloads.rclone.org/).
+
+The latest `rclone` version working for:
+| OS | Maximum rclone version | 
+|:-------:|:-------:|
+| Windows 7 | v1.63.1 |
+| Windows Server 2008 | v1.63.1 |
+| Windows Server 2012 | v1.63.1 |
+| Windows XP | v1.42 |
+| Windows Vista | v1.42 |
+| macOS 10.14 (Mojave) | v1.63.1 |
+| macOS 10.13 (High Sierra) | v1.63.1 |
+| macOS 10.12 (Sierra) | v1.56.0 |
+| macOS 10.11 (El Capitan) | v1.52.0 |
+| macOS 10.10 (Yosemite) | v1.49.0 |
+| OS X 10.9 (Mavericks) | v1.42 |
+| OS X 10.8 (Mountain Lion) | v1.42 |