Deleting images from a file - growing file

Hello all.
I want to ask how to remove object / image from LO Writer file completely.
I create a long-term file from which I periodically delete or replace images.
Unfortunately, the images do not delete completely. They disappear from the workspace but do not disappear from the file. The file is still growing. Even after deleting everything from this file leaving 1 blank page the file has 25 MB.
This also has a negative impact on the time of exporting the file to pdf.
Can this be remedied?

I already thought that a good lead unfortunately not. I don’t have change tracking enabled. Thank you for your involvement Mike.

Do you use change tracking (and have it not shown)?

Please don’t “answer” (which is for providing solutions) when what you needed is comment (and possibly edit of the question itself to add information that change tracking is checked to be disabled).

I suppose that only providing the file to analyze (upload somewhere and send a link here) could help.

ups, I am so sorry I didn’t know. Should I delete my answer and insert it as a comment?
Here is the file i I deleted all objects from 4 to 18 pages.
link text

This is tdf#131438; however, even though it has one truly unused image inside, there’s another “problem” in your document: your Default page style references the other cover image for 2018, which would not be deleted for that reason, even if there were no that bug.

You may take the fixed file from

(yes, please delete the answer, and edit the question to add the “change tracking not enabled” info)

wow, thank you so much Mike. Could you briefly describe how you fixed this problem so that I can fix it myself in the future? Until now, I had to create the file again and set the whole template all the time. Forgive me but I still don’t understand how one image made a 5MB file from a 25 MB file.

EDIT: sorry, I didn’t look here link text
i’m not english speaking and i didn’t fully understand your answer.

Thank you so much.

I opened the document as ZIP file; opened “styles.xml”; looked through the list of draw:fill-image elements; searched for occurrences of each of them (draw:name) in the same file; noted those that either didn’t appear anywhere, or appeared in bitmaps where fill was “none”; removed the elements noted; removed related files from Pictures subfolder in the ZIP.

Thank you, I will try to fix the file myself.