Page Comparison

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If the page you want to add something to does not have an extensionPoint on it, the process is simple:

1. Create a new ticket specifying the page the extPoint will be on
2. Add the point to your local copy and test it out
3. Create a patch and attach that patch diff to the ticket
4. Wait for a developer to review your patch for consistency checks
5. Apply the patch to trunk and the latest branches/1.x.x if desired
6. Close the ticket and reference the changeset

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How to add a Gutter extension point ?

https://wikiopenmrs.openmrsatlassian.orgnet/wiki/display/docs/Adding+a+Gutter+extension+point