Recap:
With this datapack is it possible to mine spawners. It's possible to choose if it's important to mine with silk touch or not, you can change that in the Mineable Spawners menu. It's also possible to enable/disable fortune. But fortune III can be a little bit OP on spawners, so it's possible to customize the fortune for each level in the MS menu. You can set the chance for each amount of blocks that you can get. Look to the pictures to see how it looks :D

It's recommended to use this datapack with a craftable spawn egg datapack. That will make it possible to make 'custom' spawners.

Important:
It's not possible to mine already mined spawners with fortune, so it's not possible to get unlimited spawners (you get than always 1 spawner).

The mobs that spawn don't have items in their hand.

This datapack can have bugs, please report them :D

This is a really easy to use datapack, so the tutorial isn't long.

Mineable Spawners menu:
/function ms:menu

Menu information:
It's possible to enable/disable silktouch/fortune in the settings tab.
When fortune is enabled, there will be a new tab added in the MS menu, 'Fortune menu'.
In the fortune menu is it possible to change the chances for each fortune level.

Changing chances important information:
The chances goes from high to low in the amount of spawners. If you want to apply the changed chances to the already existing spawners that are loaded in, than you need to go to the fortune menu and than click on '(Apply changes to already existing spawners).
In this datapack is fortune 3 = fortune 2 and fortune 2 = fortune 1 on default, the two fortune's are different so it won't change the default fortune of minecraft.

Few examples on how the system works:
Fortune 1:
1 spawner: 100%
2 spawners: 100%

You get than always two spawners

Fortune 1:
1 spawner: 100%
2 spawers: 50%

It's a one 50% chance to get two spawners if not you get immediately one spawner. The chance on two spawners is than really low.

Minecraft default fortune:
1 spawner: 66%
2 spawners: 33%

It's a 33% chance to get two spawners, than 66% chance one spawner. The loop will go over and over until one of the procents succeeds.

If you have questions you can always ask them :D

For using this datapack is this information not important.

So far I know are there two ways to make a Spawner datapack. Making it with loot tables or with a tracking system of armor_stands/area_effect_clouds. I choose for this datapack the second option otherwise it was not possible to make that custom fortune.

For making this datapack I had use an already existed datapack as inspiration source, because I wanted to make a tracking system. And that datapack had already one, so I used that datapack as inspiration to make my own tracking system. And it seems for me a little bit unfair to not give credit to that creator. I am talking about the Silk Touch Spawners Datapack from Hielke.

His datapack: https://www.planetminecraft.com/data-pack/silk-touch-spawners-datapack-1-13/