The scrollbars disappear when multiple Editor tabs are open and the script has long lines.
Steps to replicate:
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1. Start SQL Navigator
2. Log in to the Database (an empty sql editor appears)
3. Press CTRL+ALT+O and search for a package that has very long lines
4. In the search results list: double click a package body and wait for it to load in the object editor
5. Press CTRL+M to open up a new sql editor.
6. Type in anything (the scrollbar then disappears in the sql editor).
7. Click back on the object-editor-tab: (The scrollbar disappears in the object editor).
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