I am having the same exact issue. One workaround I have found for the time being is to use browser.tabs.sendMessage or browser.runtime.sendMessage.
For example if popup.js is updating the local storage and your content.js wants to listen to those changes you could send a message after updating the storage or even pass in the new storage itself.
// popup.js
// notify current tab with new settings
browser.tabs.query({ active: true, currentWindow: true }, (tabs) => {
	 browser.tabs.sendMessage(tabs[0].id, newSettings)
})
Afterward, you can listen to this message notifications like so:
// content.js
browser.storage.local.get(['settings'], (result) => {
console.log(result.newSettings)
})
Pondorasti
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution
Last seen
User for
From
Bucharest, Romania
Post
Replies
Boosts
Views
Activity
I am having the same exact issue! The only workaround I've found to work reliably is to add a minimum dragging distance to my gesture.
DragGesture(minimumDistance: 20)
Since the minimumDistance for ScrollViews is lower than the DragGesture, the scroll will always have priority. Unfortunately I did not found any way to achieve simultaneous gestures.