LibreOffice Calc sheet very slow, possibly due to X?

Version: Version:
Build ID: 40(Build:2)
CPU threads: 8; OS: Linux 4.19; UI render: default; VCL: gtk3;
Locale: en-US (en_US.UTF-8); UI-Language: en-US
Calc: threaded

Hardware: KVM virtual machine allocated 8 CPU cores and 77GB RAM, 31.7 GB in use. NVIDIA GTX1080 GPU passthrough.

LibreOffice in general been very slow for me over the past year or so. The current example frustrating me is 14.2kb .ods file. Every time I enter an “x” into a cell and press enter, it takes a full second or two to get to the next cell.

This seems unreasonably slow compared with my past experiences with spreadsheets. There are a couple of conditional formats added to the cells, but it would surprise me if these slowed things down by more than a small fraction of a second.

I notice that X CPU usage spikes when I hit enter after inputting text (from 1% to 12%).

Zoom and scroll operations are also quite slow, and they also spike X CPU to 12%

Do you have condicitional formats?