Amolith opened 
The <title> element is rendered in the base template
pkg/web/templates/base.html
This Go source file passes the title into the base template. pkg/web/webui_bugs.go
These contain examples of how to set the title. Check commits vs commit especially for examples of how to do bugs vs bug.
- pkg/web/webui_about.go
 - pkg/web/webui_blob.go
 - pkg/web/webui_branches.go
 - pkg/web/webui_commit.go
 - pkg/web/webui_commits.go
 - pkg/web/webui_git.go
 - pkg/web/webui_helpers.go
 - pkg/web/webui_home.go
 - pkg/web/webui_overview.go
 - pkg/web/webui_tags.go
 - pkg/web/webui_tree.go
 
The bug page's meta could be a truncated snippet of the bug's body and the bug list's meta could be the truncated project description.