I've been missing these for a while, there's another post about this same issue but it didn't solve my problem, is there a way to make these visible again? they made it very easy to edit values.
There are four buttons in the bottom left corner of the Timeline Panel. The first two turn the switches and modes columns on or off. Just click them. I usually edit with both turned on (they will be blue). It takes much less time to click on those buttons than to dig through the Columns menu.