Just 'snap' a plain timer based on Java.
(You are welcome to transform it ...)
Take an existing tea-timer app and create a SNAP for Ubuntu/Linux with it.
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New EDITION 2022
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https:/
( Linux / Mac OS / Windows )
... or get your free trial version
https:/
https:/
read:
https:/
https:/
view:
https:/
try:
sudo snap install ttimer
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View full history Series and milestones
ttimer0.0.2 series is the current focus of development.