Can’t export or print to pdf

I’ve been building this file for a while, making PDFs with no problems but now, with no significant changes that I’m aware of the pdf export process gets snagged on the first page. I have to shut off LO. Same with trying to print to pdf.
Any thoughts? I saw a recommendation on the forum for making SU file size smaller using a thom thom’s cleanup3 extension plug in. Can users verify that this is safe?

Try exporting from the second page onwards. That would tell you if it is something bad on page one. If it might be, make a new second page and copy things from page one to the new page, trying an export now and then, until hopefully you have everything you need on page two, and it’s still exporting ok. Then delete page one.

Like Colin says. But for me it did help me once to save the LO file as a newly named file; if it works you can delete the erroneous file and rename the new file to the original name. However I did save the SU file also to a new SU file. Later I did rename them both to the original files.

About the SY file size, make a duplicate of the SU file and try it on the copy.