2 ms·
In HTML 4.01 and XHTML "_blank" was an illegal ID, so a frame could not use it. Therefore, there was no chance of breaking existing code. "blank" however, could
by Someone1234 2y ago
In HTML 4.01 and XHTML "_blank" was an illegal ID, so a frame could not use it. Therefore, there was no chance of breaking existing code. "blank" however, could be in use when they introduced this feature and break existing pages.
This all changed in HTML5 when IDs could start with special characters like "_".