The implementation example shown below is available in the demo asset. We recommend consulting them for a better understanding

Implementation of the functionalities of increasing and decreasing the font size 

1.Create the screens actions

a) Create the screen action to call the action "FontSizeDecrease". Nominate it "DecreaseFontSize".

b) Create the screen action to call the action" FontSizeIncrease". Nominate it "IncreaseFontSize".

2.Call the Action

a) Open the screen action previously created in 1.a), and drag and drop the action "FontSizeDecrease ", inside of the action.

b) Open the screen action previously created in 1.b), and drag and drop the action "FontSizeIncrease ", inside of the action.

3.Trigger the screen action

Create two buttons to trigger the previous actions, when clicked the font of all applications will increase or decrease.