Issue Navigator Plus is definetly for you if you have
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Jira Core or
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Jira Software licence and ...
you are just getting to know
JIRAJira
you are heavy users of it but
use Excel and JIRA simultaneouslymiss some Excel-specific features from JIRA like
an Excel-like view of their issues
an Excel-like way of editing issues
copy-paste (also to/from MS Excel/Notepad)
an Excel-like way of filtering and sorting issues (without JQL knowledge)
column freezing
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If you can't find the feature you are looking for, please feel free to let us know and we'll try to implement it as soon as possible!