When one tries to execute a SQL statement in a connection-less worksheet (like right after opening a SQL File), SQL Developer, will prompt you to chose a connection form a dropdown. In previous versions (works in 3.0.04.34), this dropdown would be defaulted to the last connection used. This appears to be broken in version 3.02.09.30, where it's now always defaulting to the first item in the list.
This may be a small thing, but it's an annoyance when one has to run a bunch of SQL from a dozen or so separate files to have to pick the connection every time.
Steps to reproduce:
1. Start with two unconnected worksheet tabs. Opening two SQL files is an easy way to do this.
2. Hit Run Script in the first worksheet. Choose your desired connection from the prompt and run the SQL.
3. Hit Run Script in the second worksheet. The prompt ought to default to the connection you picked in step 2, but it doesn't.
SQL Developer QA already logged a bug for this: Bug 13952913 - REGRESSION: CONNECTION SELECTOR CAN NOT REMEMBER THE LAST CHOICE
And it was reported earlier in this forum: Re: Bug 3.2.09: Open a connection via Worksheet Icon Alt-F10 forget selcted
Initially I was surprised the regression did not get fixed right away, but apparently...
1. There is some other clean-up involved before last used connection name loading can be re-enabled.
2. Someone must agree with the first part of your This may be a small thing, but it's an annoyance statement. After all, we do have a scroll bar!
3. Another feature enhancement in the queue may be grouped together with the clean-up effort.
An example of (3) might be something like Bug 12696123 - UI_CLEANUP: CONNECTION SELECTORS SHOULD SHOW HIERARCHICAL CONNECTION FOLDERS
SQL Developer Team