Tried on several accounts and on several standard reports, disabled Da Vinci extension and the issue disappeared:
Fixed for the next release.
Great thank you!
This is clearly my fault - I will merge this bug with another entry I just got. Please see here: https://support.davinci.tools/communities/1/topics/814-ga-breakingmergingmoving-field-headers
No worries Stephane thank you!
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