Curse user glaubemich reported an issue with BuyEmAll in comments:

Hello, I am a Chinese player. Thank you for creating the exquisite addons. This addons has accompanied me in many WoW versions

Today, after updating the latest v11.0.2.0, I found that the window at the bottom of the trading window was missing when I entered the game. It seems that the addons have failed. I reinstalled the plugin and deleted WTF, but it still did not appear

Then I started to investigate whether there was a conflict with addons

I found a conflict between Merchant Plus and BuyEmAll for The War Within. After I turned off BuyEmAll, the Merchant Plus tag appeared and everything was normal. Then I went to participate in the raid, but I didn't see that BuyEmAll had been updated. Unfortunately, I am no longer able to go online for testing. I hope you can pay attention to this issue

I haven't confirmed this yet, but will investigate.

I couldn't reproduce any issues with BuyEmAll. Will leave this open for a week or two the author to post more info.