When examining the URL address (your screenshot, above) from left-to-right . . . and you reach -event/?utm, that ?utm portion (and then on, from left to right) means: the Google Urchin Tracking Monitor is probably involved.
Try . . .
Reproduce your steps, to get Brave Browser to go to the URL address shown in your screenshot, above.
When at the ‘givesmart.com’ website, set all of the Brave Browser site-specific Shields (Lion icon) settings to highest strength: Shields UP, Trackers & Ads blocked (Aggressive), Cross-site cookies blocked, Fingerprinting blocked.
In a Brave Browser > New Window, go to: brave://settings/shields
- Disable:
Auto-redirect AMP pages(AMP - Google’s Accelerated Mobile Page) - (Alternate setting for older Brave Browser versions, try: Disable
Enable De-AMPatbrave://flags) - Disable:
Prevent sites from fingerprinting me based on my language preferences - Trackers & ads blocking:
Standard - Enable:
Upgrade connections to HTTPS(HTTPS EVERYWHERE toggle switch) - Enable:
Block scripts - Block fingerprinting (aka
Fingerprinting blocking):Strict, may break sites - Block cookies (aka
Cookie blocking):Only cross-site
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Next, go to: brave://settings/content
Scroll down, past Additional permissions to Content . . . and set:
- Pop-ups and redirects:
Don't allow sites to send pop-ups or use redirects
Close that window.
Reload the ‘givesmart.com’ webpage.
If the ‘403 error’ remains, then, in a Brave Browser > New Window, go to: brave://settings/shields
- Trackers & ads blocking:
Disabled
Close that window.
Reload the ‘givesmart.com’ webpage.
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