/usr/share/gnucash/gtkbuilder/ is in gnucash-common 1:2.6.1-2.
This file is owned by root:root, with mode 0o755.
..
/usr/share/gnucash/gtkbuilder/assistant-ab-initial.glade
/usr/share/gnucash/gtkbuilder/assistant-acct-period.glade
/usr/share/gnucash/gtkbuilder/assistant-csv-account-import.glade
/usr/share/gnucash/gtkbuilder/assistant-csv-export.glade
/usr/share/gnucash/gtkbuilder/assistant-csv-trans-import.glade
/usr/share/gnucash/gtkbuilder/assistant-hierarchy.glade
/usr/share/gnucash/gtkbuilder/assistant-loan.glade
/usr/share/gnucash/gtkbuilder/assistant-qif-import.glade
/usr/share/gnucash/gtkbuilder/assistant-stock-split.glade
/usr/share/gnucash/gtkbuilder/assistant-xml-encoding.glade
/usr/share/gnucash/gtkbuilder/business-options-gnome.glade
/usr/share/gnucash/gtkbuilder/business-prefs.glade
/usr/share/gnucash/gtkbuilder/dialog-ab.glade
/usr/share/gnucash/gtkbuilder/dialog-account-picker.glade
/usr/share/gnucash/gtkbuilder/dialog-account.glade
/usr/share/gnucash/gtkbuilder/dialog-bi-import-gui.glade
/usr/share/gnucash/gtkbuilder/dialog-billterms.glade
/usr/share/gnucash/gtkbuilder/dialog-book-close.glade
/usr/share/gnucash/gtkbuilder/dialog-choose-owner.glade
/usr/share/gnucash/gtkbuilder/dialog-commodities.glade
/usr/share/gnucash/gtkbuilder/dialog-commodity.glade
/usr/share/gnucash/gtkbuilder/dialog-custom-report.glade
/usr/share/gnucash/gtkbuilder/dialog-customer-import-gui.glade
/usr/share/gnucash/gtkbuilder/dialog-customer.glade
/usr/share/gnucash/gtkbuilder/dialog-date-close.glade
/usr/share/gnucash/gtkbuilder/dialog-employee.glade
/usr/share/gnucash/gtkbuilder/dialog-file-access.glade
/usr/share/gnucash/gtkbuilder/dialog-fincalc.glade
/usr/share/gnucash/gtkbuilder/dialog-import.glade
/usr/share/gnucash/gtkbuilder/dialog-invoice.glade
/usr/share/gnucash/gtkbuilder/dialog-job.glade
/usr/share/gnucash/gtkbuilder/dialog-lot-viewer.glade
/usr/share/gnucash/gtkbuilder/dialog-new-user.glade
/usr/share/gnucash/gtkbuilder/dialog-object-references.glade
/usr/share/gnucash/gtkbuilder/dialog-options.glade
/usr/share/gnucash/gtkbuilder/dialog-order.glade
/usr/share/gnucash/gtkbuilder/dialog-payment.glade
/usr/share/gnucash/gtkbuilder/dialog-preferences.glade
/usr/share/gnucash/gtkbuilder/dialog-price.glade
/usr/share/gnucash/gtkbuilder/dialog-print-check.glade
/usr/share/gnucash/gtkbuilder/dialog-progress.glade
/usr/share/gnucash/gtkbuilder/dialog-query-view.glade
/usr/share/gnucash/gtkbuilder/dialog-report.glade
/usr/share/gnucash/gtkbuilder/dialog-reset-warnings.glade
/usr/share/gnucash/gtkbuilder/dialog-search.glade
/usr/share/gnucash/gtkbuilder/dialog-sx.glade
/usr/share/gnucash/gtkbuilder/dialog-tax-info.glade
/usr/share/gnucash/gtkbuilder/dialog-tax-table.glade
/usr/share/gnucash/gtkbuilder/dialog-totd.glade
/usr/share/gnucash/gtkbuilder/dialog-transfer.glade
/usr/share/gnucash/gtkbuilder/dialog-userpass.glade
/usr/share/gnucash/gtkbuilder/dialog-vendor.glade
/usr/share/gnucash/gtkbuilder/gnc-date-format.glade
/usr/share/gnucash/gtkbuilder/gnc-frequency.glade
/usr/share/gnucash/gtkbuilder/gnc-plugin-page-budget.glade
/usr/share/gnucash/gtkbuilder/gnc-plugin-page-register.glade
/usr/share/gnucash/gtkbuilder/gnc-plugin-page-register2.glade
/usr/share/gnucash/gtkbuilder/gnc-recurrence.glade
/usr/share/gnucash/gtkbuilder/gnc-tree-view-owner.glade
/usr/share/gnucash/gtkbuilder/window-autoclear.glade
/usr/share/gnucash/gtkbuilder/window-reconcile.glade