Hello again!
This time an interaction between your Treated Wood Crafting Table, and the mod Inventory Sorter by cpw
Steps to reproduce:

• Place any item(s) in crafting grid, retaining at least 1 more in player inventory or SideStorage for table
• Use hotkey (def: Middle-Click) to attempt to sort either inventory of Table (mouse hovering them)
• Watch in horrified amazement as the stack in the crafting grid, increases by TOTAL COUNT of that item present in the (storage slots + Players inventory)

MC 1.15.2
ED - 1.0.19-b3
Inventory Sorter - 17.0.0

Was going to report it to other author as well, but their project description seems to have a clue as the issue and hopefully gives you an idea of how to fix on your end -

/inventorysorter [arg]

It interacts with the last container you middle click sorted (or attempted to), to allow you to manipulate the container blacklist. These are containers that don't respect middleclick sorting for one reason or another (typically where a special slot containing a special item is not properly marked read only, allowing for it to be duped instead).

And yes, I followed his instructions to blacklist the table, to no effect. (Command ran properly, stating success in blacklisting, but table still dupes)

Hmm, I am pretty sure cpw knows what he is doing - this must be an issue with the crafting table. I may get time this weekend to take a look into this. Thanks for the hint already!

Ok, quick update about the first impression, I made in 1.14.4 a check (as my code is almost identical), and cannot reproduce it there. So cannot be much to find that problem in 1.15.2.
(edit -> And, boooom, happens when the items are identical with tag - and that also in 1.14, oh man).

--> It's related to the crafting grid inventory, which is not the player inventory and is handled specially in the inventorysorter. I simply made a special slot type and blacklisted it via IMC, so the issue should be solved in the next version. The inventorysorter config is somehow not loaded, probably gonna make an issue or PR for cpw.

Ok, also took a glance into the inventorysorter code, could be that a definition which kind of config (server, client, both) may have to be changed there (I am not sure there), so cpw is informed.
(issue is cpw/inventorysorter#88).

Alright, the version 1.0.19-b4 contains the inventorysorter blacklisting for 1.15.2.
I commented that out yet for 1.14.4 until it's clarified with cpw if can can fire a crash in the inventorysorter (had to decide here - crash is worse than duping ;/ ).
Can you double check if the issue is resolved for you on 1.15.2?

Fixed the issue for 1.14.4 at least, my experience on 1.15.2 was with a pack I was testing, will let the author know.