Description

Fixes a few end-of-document bugs:

• rectForOffset had an incorrect!= instead of a< check for the end of the document.
• mouseDown needed to be looser on finding content runs for the end of documents.

Adds test cases that would have caught both these bugs.

Related Issues

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Checklist

• I read and understood thecontributing guide as well as thecode of conduct
• The issues this PR addresses are related to each other
• My changes generate no new warnings
• My code builds and runs on my machine
• My changes are all related to the related issue above
• I documented my code

Screenshots

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