Fueling with light bulbs and auto pause

When in a world alone, it is quite difficult to add light bulbs to lanterns or miner hats. I've found both objects need to be in top inventory (won't work if either is in the bookbag), and then I can only add one light bulb at a time, as each time I go into my inventory the game auto-pauses. So I choose "add fuel," then click out of my inventory, and the action will be successful most of the time. However, occasionally, even when both are in top inventory, the "add fuel" doesn't work.