Openlayers is a very nice package for working with maps.
My Spring Boot, Angular and Leaflet SPA has a vendor.js file of 4.2Mb. Replacing Leaflet by Openlayers 5 gives a vendor.js of 6.8Mb. Noticed differently: adding Openlayers to a bare Angular SPA increases the SPA by about 3Mb.
When I see many examples at https://openlayers.org only 2 files are included: ol.css and ol.js. When downloading the Openlayers v5 zip, then I can see that the files are only 4kb and 640Kb.
Why has the Single Page Application (SPA) download size increased by about 2.6Mb? Other *.js files increased also a bit. The application did not change.
I used the "npm install ol --save" to add Openlayers v5 to the Angular SPA.
Of course I can use the ng build --prod to optimize the build (sizes).
@Mike - thank you for pointing the way!
When building for production with --prod any doubts vanished. The total size is about 1.5M! That's OK!