On Windows 10, /equip command results in frame rate reduction.

Platform:
Windows

ISP:
Telenor

Type of Internet Connection:
Optic Fiber

Internet Connection Speed:
500 Mbit/s

Date & Time:
Various

Frequency:
Always

Character Name:
Naryun

Race:
Hume F

World:
Valefor

Main Job:
Corsair

Support Job:
Ninja

Area and Coordinates:
Port Windurst (Mog House)

Party or Solo:
Solo

NPC Name:
None

Monster Name:
None

Steps:
This bug only appears on Windows 10, and does not happen on other versions of Windows. It started happening around March 2020.

When using an /equip command, a short but noticable frame rate drop occurs. The more items the game has to search through in order to find the item, the greater the drop in frame rate.

For greatest effect, ensure all wardrobes are full, and try to equip several items located in Mog Wardrobe 4, without specifying which Wardrobe.

Example macro:
/equip head "Malignance Chapeau"
/equip body "Malignance Tabard"
/equip hands "Malignance Gloves"
/equip legs "Malignance Tights"
/equip feet "Malignance Boots"

I have not observed this. is your windows build current?

It's up to date, yes. I've asked others to try it out as well and they've been able to confirm it happens to them too.