This extension sums up the remaining time estimates shown in a scrum board of Jira
Atlassian Jira's has a feature to capture estimations and remaining estimates in issues. You can configure Jira to show these numbers on the issue cards in scrum board.
I found it useful to see the sum of all issues for each column. Unfortunately, Jira lacks such a feature.
When turned on, this Chrome extension will calculate the sum of "remaining estimates" for each column, taking into account all issues being displayed. If you apply a filter, the sum will be calculated only for the issues matching your filter settings.
The extension was tested with Jira cloud and with Jira 7.3.8. Happy to get your feedback!