How to use matjectNEXT? BETA
Warning
matjectNEXT is still in BETA.
It's not intended to be used by normal people.
- It may not work properly for all.
- Marketplace packs are not supported. Don't put them on top of the list.
- manifest.json with comments are not supported (like /**/ and //)
- Manifest has to be fully correct in order to work.
"You" should also... 
- Have understanding of basic English.
- Be able to "read".
- Have common sense.
- Know that, "Command Prompt/Terminal ≠ Virus"
Put the shader you want to use on top of activated global resource packs.
Open
matject.In the main screen, press [3] for "matjectNEXT".
Wait for it to complete manifest check.
TIP
You can disable manifest checker from settings. Although not recommended.
If everything went good, it will show details of top (first) resource pack from global resource packs.
Press [Y] to confirm replacement/injection. [N] to cancel.After injection, it will say "Sync OK" and ask you to monitor for changes. It's optional.
Simply, it will see if you modified resource packs and automatically bring up the injection screen for you.
This is useful when you want to test multiple shaders in short period of time since it will keep scanning as long as it's open.
TIP
The "sync" part checks what pack you have on top. And injects it/restores to default or whatever is needed to make Minecraft adjust with current top pack.
You can quit after sync is OK.
Just allow matjectNEXT to sync once whenever you make any changes to resource pack which may alter shaders. (if you know what I mean)