File grows with every save

Version 2.4.2 (1032)
My problem: The file grows at each store. No multiple-master (Not yet). The whole thing escalated so far until the smallest file operation glyphs causes to crash. So it is impossible to work with the program. Then, the file size is 7.3 MB (again: no MM font). The Style Regular has three Masters at same glyph number and the file size is 3.9 MB.

The pure open and save makes further swell the size. What’s going on…? It is mysterious…

What can I do to properly save the file where I work a couple years. Is there any other file operation to normalize the glyphs-file again?

Can you send me the (big) file (to support at this domain)?

Has my email arrived?

Unfortunately not.

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