Zend certified PHP/Magento developer

What is the deal with the select all button flaking out on me?

I need to clean up my gmail messages but I can’t find out how to select all emails from search criteria to delete- I can only select all from the first page.

I clicked on one of my labels and there was a button to select all messages which is what I wanted.

I had 10k+ emails with that label.

I selected all and tried to delete but it left around 2k remaining and now when I go back to the label there is no button to select all. It just disappeared with no warning, error, or explanation.

Its truly excruciating, I can’t click through 100s of pages deleting each one.

Is this a UI bug or something?