There's a new "change what the share button does" in the Capture & Share settings screen.

Home button=> settings => Preferences => Capture and Share

Hope thats what your looking for!

try changing the length in capture and share go to capture settings and you can set how long you want to record

What version of Xbox OS you'r using?

After OS version - 10.0.18363.7194 (19h1_release_xbox_dev_1910.18363.7194.190929-1945) Release date 10/8/2019; whe got the
new feature:

Flexible capture settings

You now have more control over what gets captured and recorded in games. In Settings > Preferences > Capture & share, choose between “Captures by me,” “Captures by me or games,” and “Don’t
capture.”

Try to change that.

I'm Samy an independent advisor

How are you, Stephen?

When you connect the external hard drive to your console does a screen appear asking you to format the drive to record captures? And have you also set your preferences to use the hard drive?

Press the Xbox button  to open the guide, and then select Profile & system > Settings > Preferences > Capture & share.

Select Capture location, and then choose a destination for your game clips and screenshots.

To start a recording>

Start your game. Press the Xbox button to open the guide.

Select Capture & share > Start recording. Depending on your game clip resolution and available storage space, clips can last up to 10 minutes (capturing to internal storage) or 1 hour (capturing to external storage).

To end the clip, open the guide and press the X button . You'll get a message when your clip is saved.

Hi there you can change how long you want to record clips in settings just go to preferences then capture and share and select record what happened and change the time from there hope that helps