In your Template Editor, go into Template Settings->Display Options and locate PDF Options:
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It will look like this:

(The same controls exist per-report via the Report Settings.)

Here's more about each setting:

Display Table of Contents - turns on/off this thing:

Display Summary - toggles the linked list of defects that shows up before the body of the report:
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Page break sections - Determines if you want each section to start on a new page:

Page break comments - If enabled, comments will shift to the next page instead of being split up mid-comment: