QtWebkit asserts on an URL within a stylesheet that has a "#"

Within Trojita I open an email with a HTML attachment. This attachment causes QtWebkit to assert.
Resource:
https://ci4.googleusercontent.com/proxy/-shEvx-z5X_fEDdygs_6-SdWItpUTEcgMhdi64S2gEQdlAw7AgDLgZgL9knwTZcLnco2HBKyc3r6-IyG2unMtUnM5sWrGcndeo8hVM0DtNVTZs1l-XeGQZwZSfEmbsM=s0-d-e1-ft#https://www.gstatic.com/images/icons/material/system/1x/reply_black_20dp.png
URL:
https://ci4.googleusercontent.com/proxy/-shEvx-z5X_fEDdygs_6-SdWItpUTEcgMhdi64S2gEQdlAw7AgDLgZgL9knwTZcLnco2HBKyc3r6-IyG2unMtUnM5sWrGcndeo8hVM0DtNVTZs1l-XeGQZwZSfEmbsM=s0-d-e1-ft
ASSERTION FAILED: resource->url() == url.string()