A user needed help making the first tab open by default on their product page using the Impulse theme. The issue was resolved quickly with community assistance.
Solution provided:
theme.liquid file</body> tagMultiple respondents offered the same solution approach, providing code snippets to implement the default tab behavior. The original poster confirmed the solution worked successfully and marked it as resolved.
Status: Resolved - the user successfully implemented the fix and thanked the community for the quick response.
UPDATE: SOLUTION FOUND! Thanks to everyone who responded so fast 
Hello! Would love some help with coding, please.
How do I make the first tab open by default on my product page? My website theme is Impulse. I’m not confident with which code to edit - please help!
@HelenVAC ,
Step 1: Go to Admin → Online store → Theme > Edit code
Step 2: Search for the file theme.liquid
Step 3: Add this code before tag
If it helps you, please like and mark it as the solution.
Best Regards 
Hey @HelenVAC
Follow these Steps:
Go to Online Store
Edit Code
Find theme.liquid file
Add the following code in the bottom of the file above tag
RESULT:
If I managed to help you then, don’t forget to Like it and Mark it as Solution!
Best Regards,
Moeed
ah you’re the best! Thanks for responding so quickly - this worked a treat
