Dictionary freezes LO (v5.2.4 and above)

As the title says, my LO program (Writer, Calc, or Impress) freezes for a second or two when right-clicking on a auto-correct flagged word. Instead of bringing up the list of correction suggestions as usual, the whole program freezes for 1-2 seconds, sometimes longer, and only then the menu appears.

The freeze happens in both 32 and 64-bit versions, v5.2.4 and above, while v5.1.6 is fine.

I’m on a HP ProBook 4740s laptop. Windows 10 Pro x64 (English). Intel i5 3210. 6GB RAM. Intel 535 SSD.

Any suggestions as to why it might be happening?

Thanks!