dark-mode: Change miscolored popover arrow colors.
dark-mode: Change miscolored popover arrow colors.

Fixes #8768.

synicalsyntax/zulip,showell/zulip,dhcrzf/zulip,kou/zulip,synicalsyntax/zulip,punchagan/zulip,brainwane/zulip,andersk/zulip,brainwane/zulip,jackrzhang/zulip,rishig/zulip,tommyip/zulip,shubhamdhama/zulip,synicalsyntax/zulip,rishig/zulip,dhcrzf/zulip,showell/zulip,dhcrzf/zulip,showell/zulip,kou/zulip,zulip/zulip,showell/zulip,zulip/zulip,synicalsyntax/zulip,synicalsyntax/zulip,andersk/zulip,eeshangarg/zulip,shubhamdhama/zulip,eeshangarg/zulip,synicalsyntax/zulip,jackrzhang/zulip,dhcrzf/zulip,rht/zulip,rht/zulip,kou/zulip,punchagan/zulip,rht/zulip,hackerkid/zulip,hackerkid/zulip,showell/zulip,andersk/zulip,brainwane/zulip,shubhamdhama/zulip,andersk/zulip,tommyip/zulip,dhcrzf/zulip,hackerkid/zulip,timabbott/zulip,jackrzhang/zulip,eeshangarg/zulip,rishig/zulip,tommyip/zulip,brainwane/zulip,shubhamdhama/zulip,rishig/zulip,jackrzhang/zulip,punchagan/zulip,shubhamdhama/zulip,showell/zulip,punchagan/zulip,rishig/zulip,shubhamdhama/zulip,hackerkid/zulip,timabbott/zulip,timabbott/zulip,kou/zulip,brainwane/zulip,timabbott/zulip,timabbott/zulip,eeshangarg/zulip,kou/zulip,zulip/zulip,punchagan/zulip,rht/zulip,rht/zulip,tommyip/zulip,kou/zulip,rishig/zulip,andersk/zulip,brainwane/zulip,eeshangarg/zulip,zulip/zulip,jackrzhang/zulip,punchagan/zulip,zulip/zulip,dhcrzf/zulip,timabbott/zulip,tommyip/zulip,jackrzhang/zulip,tommyip/zulip,eeshangarg/zulip,punchagan/zulip,showell/zulip,eeshangarg/zulip,andersk/zulip,dhcrzf/zulip,kou/zulip,rht/zulip,zulip/zulip,brainwane/zulip,synicalsyntax/zulip,hackerkid/zulip,hackerkid/zulip,jackrzhang/zulip,tommyip/zulip,andersk/zulip,rht/zulip,hackerkid/zulip,timabbott/zulip,rishig/zulip,shubhamdhama/zulip,zulip/zulip