Using the QGIS expression string builder, there is a preview window at the bottom that shows the pre-calculated output for the current feature selected. However, with more complex expressions, calculation can become complex and takes a while. The expression string builder can become slow or even hang. This is especially true for aggregate or (nested)
Editing an expression in such circumstances is difficult as each character entered or deleted starts calculation from the start and each time it takes a while until it becomes responsive again.
Is there a way to disable/deactivate the preview in QGIS expression string builder?