You can fire a script from the onDoubleClicked extension function on the alarm status table, the script can read the alarm notes by using code similar to this:
from com.inductiveautomation.ignition.common.alarming.config import CommonAlarmProperties
queryResult = system.alarm.queryStatus(path="*"+path+"*",state=['ActiveAcked'])
notes = queryResult[0].getAckData().get(CommonAlarmProperties.AckNotes)
system.perspective.print(str(notes))
(taken from this post Get Acknowledgement Notes - #7 by cmallonee)
Then you can use something along these lines to open that webpage in a new tab:
import webbrowser
webbrowser.open_new_tab(notes)