[Glitch] Fix alert when failing to save timeline markers in web UI
[Glitch] Fix alert when failing to save timeline markers in web UI

Port 59d943e152a36c693eddd6a6a3c1d9c956dba07b to glitch-soc

Signed-off-by: Claire <82b964c50e9d1d222e48cf5046e6484a966a7b07@sitedethib.com>

Kirishima21/mastodon,glitch-soc/mastodon,im-in-space/mastodon,Kirishima21/mastodon,glitch-soc/mastodon,im-in-space/mastodon,glitch-soc/mastodon,glitch-soc/mastodon,im-in-space/mastodon,Kirishima21/mastodon,im-in-space/mastodon,Kirishima21/mastodon