I would imagine that this happens under other circumstances too, but here's what I did:
Download Minecraft on a new computer
Open the launcher
Select Latest release
Play
Download bar appears on the bottom
The file size tracker at the beginning of the line (0MB/123.45MB) has a typo: the first number displays without a decimal point. (example: 10000MB/123.45MB instead of 100.00MB/123.45MB)
Thank you for your report!
We're actually already tracking this issue in MCL-12076, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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