Update README about HDR

README.md

@@ -47,11 +47,26 @@ If you want to use your dGPU, just set the `Adapter Name` to your dGPU and enabl
 > Apollo and SudoVDA can handle HDR just fine like any other streaming solutions.
 >
 > If you have had good experience with HDR previously, you can safely ignore this section.
+>
+> If you're curious, read on, but don't blame Apollo for poor HDR support.
+
+Whether HDR streaming looks good, it depends completely on your client.
+
+In short, ICC color correction should be totally useless while streaming HDR. It's your client's job to get HDR content displayed right, not the host. But in fact, it does affect the captured video stream and reflect changes on devices that can handle HDR correctly. On other devices that can't, the info is not respected at all.
+
+It's very complicated to explain why HDR is a total mess, and why enabling HDR makes the image appear dark/yellow. If it's your first time got HDR streaming working, and thinks HDR looks awuful, you're right, but that's not Apollo's fault, it's your device that tone mapped SDR content to the maximum of the capability of its screen, there's no headroom for anything beyond that actual peak brightness for HDR. For details, please take a look [here](https://github.com/ClassicOldSong/Apollo/issues/164).
+
+Usually Apple devices that have HDR capability can be trusted to have good results, other than that, your luck depends.
+
+<details>
+<summary>DEPRECATION ALERT</summary>
 
 Enabling HDR is **generally not recommended** with **ANY streaming solutions** at this moment, probably in the long term. The issue with **HDR itself** is huge, with loads of semi-incompatible standards, and massive variance between device configurations and capabilities. Game support for HDR is still choppy.
 
 SDR actually provides much more stable color accuracy, and are widely supported throughout most devices you can imagine. For games, art style can easily overcome the shortcoming with no HDR, and SDR has pretty standard workflows to ensure their visual performance. So HDR isn't *that* important in most of the cases.
 
+<details>
+
 ## How to run multiple instances of Apollo for multiple virtual displays
 
 Follow the instructions in the [Wiki](https://github.com/ClassicOldSong/Apollo/wiki/How-to-start-multiple-instances-of-Apollo).