add requirements page

README.md

@@ -127,13 +127,13 @@ If you find LosslessCut useful, I'm very thankful for [your support](https://git
 
 If you want to test the very latest and greatest bleeding-edge version. 1. Go to [Actions](https://github.com/mifi/lossless-cut/actions/workflows/build.yml), 2. click on the latest *Build/release*, 3. scroll all the way down to *Artifacts*. **Note:** these builds may be totally broken!
 
+## [Supported operating systems](./requirements.md)
+
 ## Supported formats
 
-Since LosslessCut is based on Chromium and uses the HTML5 video player, not all FFmpeg supported formats will be supported smoothly.
+LosslessCut uses Chromium's HTML5 video player, and not all FFmpeg supported formats and codecs are natively supported. Generally, the following formats should work: `MP4`, `MOV`, `WebM`, `Matroska`, `OGG` and `WAV`. The following audio codecs: `FLAC`, `MP3`, `Opus`, `PCM`, `Vorbis` and `AAC`. Video codecs: `H264`, `AV1`, `Theora`, `VP8`, `VP9` and `H265` (needs hardware decoder). More information about [Chromium supported formats / codecs](https://www.chromium.org/audio-video). [What's the difference between a codec and a format?](./issues.md#primer-video--audio-formats-vs-codecs)
-The following formats/codecs should generally work: MP4, MOV, WebM, MKV, OGG, WAV, MP3, AAC, H264, Theora, VP8, VP9
-For more information about supported formats / codecs, see https://www.chromium.org/audio-video.
 
-Unsupported files can still be converted to a supported format/codec from the `File` menu. (Try the "fastest" option first.) A low quality version of the file (with/without audio) will then be created and opened in the player. The actual cut/export operation will still be performed on the original file, so it will be lossless. This allows for potentially opening any file that FFmpeg is able to decode.
+Codecs and formats not listed above can still be converted to a supported format/codec from the `File` menu. (Try the `fastest` option first.) A low quality version of the file (with/without audio) will then be created and opened in the player. The actual cut/export operation will still be performed on the original file, so it will be lossless. This allows for potentially opening any file that FFmpeg is able to decode.
 
 ## Video demos
 

issues.md

@@ -21,12 +21,14 @@ LosslessCut version in the App Stores is often a few versions behind the latest
 
 They have exactly the same in-app features, except for a few platform limitations: Apple doesn't allow opening VOB files with App Store apps. Apple App Store apps run in a sandbox, and therefore need to prompt for output directory before allowing writing files.
 
-# Primer / noob guide: Video & audio formats & codecs
+# Primer: Video & audio formats vs. codecs
 
 Here's a little primer about video and audio formats for those not familiar. A common mistake when dealing with audio and video files, is to confuse *formats*, *codecs*, and *file names*. In short: A file's media format is a *container* that holds one or more *codecs* (audio/video/subtitle) inside of it. For example `.mov` is a *container format*, and `H265`/`HEVC` is a *codec*. Some formats support some particular codecs inside of them, while others support other codecs. The most common formats are arguably Matroska (often `.mkv`) and MP4/MOV (often `.mp4`/`.mov`) as well as their derivatives. Example: If you have a file named `My video.mp4`, this file most likely (but not necessarily) has the *format* `MP4`. Note that the extension of a file (in this case `.mp4`) doesn't really mean anything, and the file could in reality for example have the `MOV` format, or the extension could be `.txt`. Inside `My video.mp4` there are multiple tracks/streams, each with their own *codec*. In this example, let's say that it contains one `H264` track and one `AAC` track. In LosslessCut you can view and add/delete/modify these tracks.
 
 **Remuxing**: If you change the output format in LosslessCut and export a file, you are *remuxing* the tracks/codecs into a different container format. When you do this, the operation is in theory lossless, meaning you will not lose any codec data and the different tracks will remain exactly the same, even though the format is now different (but some format metadata might get lost due to incompatibilities between container formats). There are limitations: Some popular codecs like VP8 or VP9 are not supported in popular formats like MP4, and some popular formats like Matroska (`.mkv`) are not natively supported in popular video players like iPhone or QuickTime.
 
+Here is a great introduction to audio/video: [howvideo.works](https://howvideo.works/).
+
 # Common / known issues & troubleshooting
 
 ## The exported video has a problem

requirements.md

@@ -0,0 +1,8 @@
+# Supported OS versions
+
+LosslessCut is based on Electron which routinely drops support for old OS versions, and therefore LosslessCut will also do so. [More info](https://github.com/mifi/lossless-cut/discussions/1476#discussioncomment-5012521).
+
+- v3.58.0 [dropped support](https://www.electronjs.org/docs/latest/breaking-changes#removed-macos-1013--1014-support) for MacOS 10.14 and older.
+- v3.52.0 dropped support for Windows 8.1 and older.
+- v3.48.2 dropped support for MacOS 10.12 and older.
+- v3.48.2 dropped support for 32 bit Linux.