Simulate a right mouse click
You can right-click by holding down the left mouse button. This is useful if you find it difficult to move your fingers individually on one hand, or if your pointing device only has a single button.
Open the Activities overview and start typing Universal Access.
Click Universal Access to open the panel.
Press Click Assist in the Pointing & Clicking section.
In the Click Assist window, switch the Simulated Secondary Click switch to on.
You can change how long you must hold down the left mouse button before it is registered as a right click by changing the Acceptance delay.
To right-click with simulated secondary click, hold down the left mouse button where you would normally right-click, then release. The pointer fills with a different color as you hold down the left mouse button. Once it will change this color entirely, release the mouse button to right-click.
Some special pointers, such as the resize pointers, do not change colors. You can still use simulated secondary click as normal, even if you do not get visual feedback from the pointer.
If you use Mouse Keys, this also allows you to right-click by holding down the 5 key on your keypad.
In the Activities overview, you are always able to long-press to right-click, even with this feature disabled. Long-press works slightly differently in the overview: you do not have to release the button to right-click.