With stable network connection, your answers are auto-saved. You can check if your answers are saved following the instructions below.
"Save Answer/Saved" button
You can select "Save Answer" next to each question or "Save All Answers" as you work.
When you save an answer, Saved appears in the question's row.
Use of Content Editor
You can expand the editor window to fill the browser window.
Once the editor window is expanded, the “Save Answer/Saved” button would be hidden.
Please consider clicking the same button as below to escape the Fullscreen view and checking if your answers are saved.
For more, please refer to Blackboard Help: What Does the Editor Do?