When selecting a sentence with a citation in the middle, the selection gets reseted as soon as the citation is included in the selection. This interferes in the select/copy/cut/paste workflow, making the editing experience less fluent. The issue is illustrated below:
The problem seems to be present in Firefox, but not in Chrome so there may be abrowser-specific aspect to it. In addition, the issue does not seem to happen on Visual Editor.
This issue was mentioned in a discussion, translating 1936 Cansiglio earthquake from English to Italian.