TypeError: useragent.version.split is not a function

[jfoclpf]

This error is popping up several times in the error log

at Layer.handle [as handle_request] (/var/www/autocosts.prod/node_modules/express/lib/router/layer.js:95:5)
78|autocos |     at /var/www/autocosts.prod/node_modules/express/lib/router/index.js:281:22
78|autocos |     at Function.process_params (/var/www/autocosts.prod/node_modules/express/lib/router/index.js:335:12)
78|autocos |     at next (/var/www/autocosts.prod/node_modules/express/lib/router/index.js:275:10)
78|autocos | 03-05-2022: TypeError: useragent.version.split is not a function
78|autocos |     at isCSP3compatible (/var/www/autocosts.prod/bin/server/renderPageCC.js:168:48)
78|autocos |     at Object.render (/var/www/autocosts.prod/bin/server/renderPageCC.js:67:34)
78|autocos |     at /var/www/autocosts.prod/bin/server.js:279:20
78|autocos |     at Layer.handle [as handle_request] (/var/www/autocosts.prod/node_modules/express/lib/router/layer.js:95:5)
78|autocos |     at next (/var/www/autocosts.prod/node_modules/express/lib/router/route.js:137:13)
78|autocos |     at Route.dispatch (/var/www/autocosts.prod/node_modules/express/lib/router/route.js:112:3)
78|autocos |     at Layer.handle [as handle_request] (/var/www/autocosts.prod/node_modules/express/lib/router/layer.js:95:5)
78|autocos |     at /var/www/autocosts.prod/node_modules/express/lib/router/index.js:281:22
78|autocos |     at param (/var/www/autocosts.prod/node_modules/express/lib/router/index.js:354:14)
78|autocos |     at param (/var/www/autocosts.prod/node_modules/express/lib/router/index.js:365:14)