Hi!
I just found a solution for the blockage on chromium-based apps 
def displayPDF(file):
# Opening file from file path
with open(file, "rb") as f:
base64_pdf = base64.b64encode(f.read()).decode('utf-8')
# Embedding PDF in HTML
pdf_display = f"""<embed
class="pdfobject"
type="application/pdf"
title="Embedded PDF"
src="data:application/pdf;base64,{base64_pdf}"
style="overflow: auto; width: 100%; height: 100%;">"""
# Displaying File
st.markdown(pdf_display, unsafe_allow_html=True)
It makes the trick I think:
