A stroke that stays the same width does not establish where pressure information was lost. Start by checking whether Krita receives changing pen input, then compare that evidence with the brush's visible response. Those observations answer different questions.

For this Krita 5.3 check, record the tablet model, installed driver and affected preset. Keep a simple test document ready, with room for several short strokes. Avoid adjusting the global pressure curve and the preset together, because that would make the cause of any improvement unclear.

Inspect the raw input first

Open Krita's Tablet Settings and its Tablet Tester. The drawing area shows red for mouse events and blue for tablet events; the adjacent text area reports input details. Mouse events do not provide pressure sensitivity. If no blue trace appears, Krita is not accessing tablet events in that test.

Draw a short light-to-firm-to-light stroke and inspect the reported pressure changes. A blue trace establishes access to tablet events, but the pressure values still need to vary as expected. Retain a short relevant sample of the tester output with the conditions of the trial.

The tester displays raw events and ignores Krita's tablet configuration adjustments, including the global pressure curve. Do not expect changing that curve to alter the raw tester evidence. The curve affects the application's pressure response, which needs its own drawing comparison.

Compare the input evidence with actual paint

Return to the test document. Repeat the same stroke using a preset known to respond visibly to pressure, then using the affected preset. Keep size, canvas zoom and hand movement reasonably consistent. Label the swatches so the comparison remains understandable after switching tools.

If raw pressure varies and the comparison brush responds, focus the next investigation on the affected preset's intended behaviour. A brush designed to make a uniform mark is not necessarily malfunctioning. If neither brush responds, retain that separate observation instead of concluding that one preset is the cause.

If the tester lacks tablet events or changing pressure, record that result before editing brush settings. It provides a more useful starting point for tablet or input configuration support than a description that every line looks thick.

Keep the tester sample and labelled swatches together. The result of this workflow is a located boundary between incoming events and visible painting behaviour, not a promise that one successful test validates every pressure, tilt or button feature of the device.

Sources: Krita official documentation.