KDE - Shortcut taken but...by what??

Hi guys! Up until very recently, I had the shortcut Control + Shift * L assigned to Bitwarden autofill extension in Firefox. But now it no longer works. I saw that if I right click on the empty password field and choose the bitwarden extension submenu, I can get it to autofill. So Bitwarden works. Then I went to Firefox shortcut settings. Control + Shift + L was correctly assigned to Bitwarden. I tried changing it to another combination. Which was turning tricky on Control + Shift pairings. I tried just in case to set it back to Control + Shift + L, and here's the interesting part: It's not reading it. Something else is stealing the keypress, and I have no idea what it is. How can I look it up?