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ONLYOFFICE
ONLYOFFICE Docs is a free collaborative online office suite comprising viewers and editors for texts, spreadsheets and presentations, forms and PDF, fully compatible with Office Open XML formats: .docx, .xlsx, .pptx and enabling collaborative editing in real time.
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InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
Seems to have no updates since 3 years.
OnlyOffice (IMO) looks the closest like MS Office , is open source (AGPL) and handles the MS Office formats very well.
https://www.onlyoffice.com/
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