Thank you for all of your work. One minor inconvenience I've been experiencing since the addition of the plus and minus buttons is that when I click the box with the number in it I want to change, it typically doesn't highlight the number by default anymore, instead it places the cursor to the left or right of the number. It seems to highlight the values occasionally, but only rarely, perhaps there's a tiny pixel hotspot I'm just not hitting (I'm using firefox on windows 10).
For example, I used to typically click the box of the inventory number I wanted to change, it would highlight the value and easily change the value from 1 to whatever number I wished to enter by typing. Changing the value from 1 to another number is what the majority of my hours on deckbox consist of, so doing something like entering an entire booster box of cards, it saves a LOT of time when the number is automatically highlighted upon clicking.
Now, most of the time when I click, I end up on either side of the digit and change the value to 12 or 21 if I've trying to change the value from 1 to 2, for example.
Also, the plus and minus overlapping values overlapping the boxes next to them makes it very easy to accidentally click plus or minus when trying to click from the inventory value to the tradelist value, or vice versa. I think if they were spaced apart with some padding between them it could work out very well.
I think the +/- buttons are a good idea in theory as they do allow easy 1 handed touchpad or mouse-only operation without needing to touch the keyboard. I haven't tried on mobile but I assume it makes it faster there as well, as my mobile keyboard always takes a second or two to come up.