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docs/source/whatsnew/pr/prompt-update-modifications.rst

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+Prompt Rendering Performance improvements
+=========================================
+
+Pull Request :ghpull:`11933` introduced an optimisation in the prompt rendering
+logic that should decrease the resource usage of IPython when using the
+_default_ configuration but could potentially introduce a regression of
+functionalities if you are using a custom prompt.
+
+We know assume if you haven't changed the default keybindings that the prompt
+**will not change** during the duration of your input – which is for example
+not true when using vi insert mode that switches between `[ins]` and `[nor]`
+for the current mode.
+
+If you are experiencing any issue let us know.