Is there an existing issue for this?

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Description of the Issue

There is excessive rounding of corners of spinner (up/down) controls in dark mode. Compare the spin controls in light & dark modes below.

This becomes especially noticeable when spin controls are much narrower in dimensions. When they are narrower, they will be rendered as ellipses in dark mode.

Steps To Reproduce

1. Use an NPP plugin with spinner controls. For example, use the 2.4.4.1 NPP Darkmode Test Pre-release of Goto Line Col plugin.

Current Behavior

With the current version of darkmode support in Notepad++, the test pre-release version of Goto Line Col panel will be rendered in light & dark modes as below:

Expected Behavior

When this issue is resolved, the test pre-release version of Goto Line Col panel should be rendered in light & dark modes as below:

Debug Information

Notepad++ v8.8.1

Anything else?

Please see my post below for suggestions on how this issue could be resolved.