This may be more of a wish list request than a how to fix it request.
Can the cursor (pointer) be enlarged and it's color changed?
Under the Configure KyMyMoney --> Icons, there is the advice to install the Oxygen theme, but there is no suggestion concerning how that is to be accomplished. The only option displayed is "system". In theory, the Oxygen theme has been downloaded but does not seem accessible.

Currently running Linux Mint 21, Cinnamon. Current version of KMyMoney 5.1.2

Changing the theme, window behavior and cursor style is a KDE basic functionality which KMyMoney simply uses. Try running systemsettings5 to change those settings.

Hope that helps.

I'm running Mint 21, with the cinnamon desktop. Systemsettings5 does not show-up in my menu settings as i am not using KDE. Some limited KDE applications can be run under the cinnamon desktop, but I have not seen a KDE application where the cursor can be modified.

The cursor - just as other window environment settings - are provided and controlled by the window manager. Sorry, there is nothing we can do about it in KMyMoney and honestly, don't want to.

In Linux Mint, go to your Menu in left corner of the panel and select "Software Manager". After Software Manager launches and finishes building its cache, go to the search bar in the upper right hand corner and enter Breeze or Oxygen or Tango. In the results list, look for the desired icon theme and click to install it. Repeat for each of the other 2 icons. This will install those icons in the proper location in Mint and they will become available in the KMyMoney settings menu for selection.

I took a more aggressive approach, that did not resolve the cursor (pointer) concern. Basically, I downloaded (from the Mint repository) any Oxygen, Tango, Breeze applications that were available.

After downloading, I was now able to select from three available options: system, Oxygen, Tango, Breeze. (Under Settings --> Configure-KyMoney --> Icons.) The Breeze download did not show-up as an option; reason unknown. The Oxygen and Tango downloads worked, but I don't know which of those various downloads actually worked. One option to figure out which download worked, would be to remove them one by one. Oxygen and Tango now show up as selection options. Regretfully, the cursor (pointer) remains the same.

@ ipwizard: The system cursor is set to "Oxygen 05 Vibrant Red". For what ever reason, it is not being "accepted" by KMyMoney. Ironically, when I scroll-up to the very top of the title-bar the red cursor does appear.

Sorry, KMyMoney code does not play with the cursor. Regarding all the window and widget stuff it relies on KDE and Qt libraries. I have no idea how you can achieve what you are trying to do.

Upon further testing, KMyMoney recognized the Oxy-Red_Argentina cursor (pointer) themes which has the size and contrast to resolve my concerns. Again, which downloads of the various Oxygen, Tango, Breeze cursor themes actually worked is unknown.

Also interesting, the Breeze cursor is now recognized by KMyMoney. I went ahead, as a test, and installed the "breeze-cursor-theme" from the Mint repository. According the the description, this applies to the KDE Plasma 5 desktop. (I am using the Mint Cinnamon desktop.) Well, it works!

Just as an FYI, this thread was the result of upgrading to newly released Mint 21. Sometimes it takes a bit of time to reestablish some of the prior configurations, such as the cursor themes.

@ipwizard and markhm: Thanks for responding.