Gregory's Server
Imagine you come across a small but somewhat useful piece of software, written in C or C++, built using a typical buildsystem like Meson or straightforward Make. There aren't any unreasonable dependencies or version requirements either.
Think something like scdoc.
But, there's a Dockerfile in the repo (starting FROM an outdated ubuntu image, naturally), all the build instructions prominently recommend doing the build in Docker, ...
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...and all the usage instructions just as prominently recommend using a pre-built Docker image provided by them.
Should you file a bug report, where all signs point to a rather obvious issue in their code, and happen to mention that you weren't in fact using Docker, but just built the software in the natural & straightforward way, the maintainers close the report, saying that non-Docker builds are unsupported, ...
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