To use this fix, you will have to modify a core mincraft .jar file.
It is recommended that you create a new profile for that.

- Use the official launcher to download and start once the required Minecraft version.

- Go to the minecraft base folder (official launcher -> Edit Profile -> Game Directory)

- Open the "Versions" folder

- Copy the folder of the required version, adding "_modded" at the end

- Open the copied folder

- Add "_modded" after the names of the .jar and .json files there
(the end result will look like 1.7.4_modded.jar)

- Open the .json file with a text editor and replace add "_modded" to the "id" field
(the end result will look like "id": "1.7.4_modded")
Save and exit.

- Open the .jar file with 7zip, WinRAR or any other copmpatible archiver

- Copy the .class file from the "click mining fix" ZIP file  into the .jar and remove the META-INF folder

- Start the official launcher

- Click "Edit Profile" -> "Use version:" -> required version _modded

- Click "Save Profile"

- Click "Play" or "Login" to start the game. If only "Play Offline" is available, then log out and log in again to fix it.

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When using with forge and FML, be sure to add the line

-Dfml.ignorePatchDiscrepancies=true -Dfml.ignoreInvalidMinecraftCertificates=true

and mod the forge's version