To fix the issue, please ensure that the scaling in the Windows settings is set to 100%.
Otherwise, windows or buttons may appear distorted or even disappear. Additionally, this can cause unwanted effects in certain functions of Heredis.
Select Start > Settings > Time & language > Language & region:
To enlarge the display in Windows and Heredis without negatively affecting Heredis's appearance, we recommend reducing the screen resolution:
Make sure not to lower the screen resolution below 1366x768.

If Heredis is blurry display or if you need to edit the scaling of your screen resolution, check out this article:
Change scaling settings for Heredis
In addition, there are other font settings options in the Heredis preferences.
To access them, go to the Tools menu > Preferences > Heredis Preferences.
Switch to the Format tab:
Note fonts can also be configured individually in each Heredis note.