How do I undo a Home Currency Adjustment?

I think I found the answer. I believe it's simply a matter of deleting the corresponding journal entry which isdone as follows:

1. Click on the big Cog at the top right of most[1] QB Online screens, and choose Currencies under the LISTS list in the popup
   
2. For the currency in question, choose Revalue currency (under the ACTION menu to the far right of each currency line).
3. Click on the Revalue history tab to get a list of past adjustments
4. Click on the one you want, to open it.
5. Once inside, click on More at the bottom, middle, and choose Delete from the resulting popup menu

That's it!

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[1] That is as opposed to the smaller cog still high up and right-ish, but not top right, on some other QB Online screens, and also as opposed to a few screens -- j/e's for example -- where the most obvious cog is indeed top right, and is large (compared with other cogs occasionally seen from time to time, but possibly smaller than some much larger cogs that could be out there waiting, but which is in fact *not* the large, top-right cog you want here. Great UI design, Intuit. Excellent. Really superb. :-( <smh>