Inventor 2020.1 has a nice small enhancement to the Sketching environment, and that is the inclusion of a keyboard shortcut for the Horizontal command. To access the Horizontal Command in Inventor 2020.1’s sketch environment, simply press the dash key [ – ] (as shown below)
When Mousing over the commands, both Horizontal and Vertical Constraints, you will see their respective shortcuts in brackets next to the constraint. Horizontal Constraint (-) and Vertical Constraint (i)
If for some reason, your shortcut is not showing, it is pretty simple to set up yourself. Have a look at the GIF below and follow these instructions.
Right click anywhere on the Ribbon, and select “Customise User Commands”, then click on the “Keyboard” tab, now select “Sketch” from the Categories drop down. Next you will need to locate “Horizontal” and then assign the shortcut (as shown) then click “Apply”
Your shortcut will now work and display as expected.
Image credit for the keyboard: Autodesk Help