Yes, Steam client updates can be downloaded manually via HTTP, if the names of the update files are known.
In my case, Steam seems to be unable to handle the poor Internet connection. When the network gets interrupted briefly, Steam just issues an error and exits; if I start it again, it can't resume the process and everything have to be downloaded again. So I'd like to use a robust download utility that supports pause and resume (i.e. HTTP Range Request).
The files it failed to download can be found in
bootstrap_log.txt. (It is located under the directory
~/.local/share/Steam/logs on Linux). For example, this is one of the entries in the log:
Package file tenfoot_dicts_all.zip.c74a3a9beb77a280cfd8761b901a80ed0f6a3173 missing or incorrect size
To apply the updates manually:
Using your favourite download utility, download http://media.steampowered.com/client/ + package file name. In this case, it's
Put the files you've downloaded where Steam Client would. On Linux it is
And now Steam should be extracting the updates right away, without downloading them again.
Credit: aiusepsi on the r/Steam community on Reddit.
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