MailClient.exe High CPU Usage

Windows 10 Pro 64-bit English
Version 2004 (OS Build 19041.928)

eM Client (x86)
Version: 8.2.1237 (b402cf3)
2 POP3/SMTP email accounts setup
Few incoming email rules setup
10 Sub-folders setup for mail organization
Dark Mode enabled
Conversation View enabled
Not using Calendar
Only 3 contacts in Address Book
No other preferences or settings changed from defaults

CPU Usage is normal after starting the app.
After a few hours the app is using 100% of one of the CPU cores.
Is there a fix?
This is annoying because it causes my notebook fan to turn on and impacts energy consumption.

There are 2 instances of MailClient.exe running in Task Manager

Do I need to send any logs? If so, how do I do it?
Do I need to pay for PRO to get it fixed?

EmClient take a tiny bit of ram (less than 150MB) but doesn’t even take 1% on my old CPU and does run in background all day long.
Send your PC spec with the logs we might find something more useful.
I use IMAP/SMTP and sync every 5 minutes.

Computer specs:

How do I make and send the logs?

Just happened again. Restarted em Client 4 hours ago. It was fine for 4 hours, but now it is at a constant 27% CPU utilization. I can always tell when it acts up because my CPU fan kicks into high gear.

@ShaunY can you tell me how to make and send the logs?

The problem persists.

Go to Menu > Setting > Advanced > Logging > Check Every Box > Apply > Restart EmClient
Once EmClient start to take more CPU Close it and have a look at the logs.

I also see that you use MS office have you noticed a specific behavior change when you open MS Office app?