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.changeset/button-layouts.md

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+---
+"@jspsych/plugin-html-button-response": major
+"jspsych": patch
+---
+
+Button plugins now support either `display: grid` or `display: flex` on the container element that hold the buttons. If the layout is `grid`, the number of rows and/or columns can be specified. 
+
+jspsych.css has new layout classes to support this feature.