diff --git a/docs/requirements.txt b/docs/requirements.txt
index 5a27f22..491e35e 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -8,3 +8,4 @@ sphinx-gallery==0.10.1
 mne<1.5 # for building docs, since mne-bids is needed, must have lower version of mne https://github.com/mne-tools/mne-python/pull/11582/files
 openneuro-py==2022.4.0
 mne-bids==0.11.1
+nbformat>=4.2.0