Close obsolete / solved issues (second round)

### Number of issues so far: ~~6~~ ~~4~~ 3
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This is a second round of obsolete issues that can be closed due to being obsolete or having been solved.

**Remember** that my primary goal here is to drive down the number of issues so we can have a better understanding of the state of the project; what needs to be fixed, and how we should proceed going forward. 

### Obsolete PRs

Close #1623: superseded by #1856.
Close #2227: polluted pull request, non-responsive author.
Close #2379: polluted pull request, non-responsive author.

### Solved or obsolete issues:

~~Close NOT #1727: a fix has been provided.~~

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Related issues: #2568, #2809.