Many epub books use an apostrophe such as which is hex 92 and is called Right single quotation mark, it causes ereaders like Kobo to insert a spurious space after the character. The solution is to replace all hex 92 character with the hex 27 character and is called Single quote.
To do this:
1: Download and install the epub editor Sigil from https://sigil-ebook.com/sigil/download/
2: Open Calibre to view books in library.
3: Right click an affected book and choose Open Containing Folder.
4: Right click the .epub file and choose open with Sigil (or The Calibre epub Editor is very similar).
5: Often the following message will appear, allow Sigil to fix the epub file:
This EPUB has HTML files that are not well formed or are missing a DOCTYPE, html, head or body elements. Sigil can automatically fix these files, although this may very rarely result in minor data loss in extreme circumstances.
6: The book will open in Sigil and show various files such as title, jacket and a number of chapter files.
7: On the menu bar click Search > Find & Replace.
8: At the bottom of the window copy from this line and paste into the Find box, then copy ' and paste into the Replace box.
9: Ensure that the middle drop down is changed to All HTML files so the find and replace will process all individual HTML files.
10: Observe that hundreds or thousands of replacements have been made.
11: On the File menu Save the file, which will overwrite the original with the modified file.
12: Plug in USB cable to Kobo reader, at message Computer detected touch Connect.
13: The Kobo Reader drive will open showing various files and folders - just minimise or close.
14: Select the modified book and it will highlight in blue.
15: Click the Send to device button - blue arrow.
16: On the Device button choose and click Eject Device then unplug the Kobo reader.
17: Open corrected book in Kobo reader and check the there are no spaces after apostrophes (now single quotes).
To do this:
1: Download and install the epub editor Sigil from https://sigil-ebook.com/sigil/download/
2: Open Calibre to view books in library.
3: Right click an affected book and choose Open Containing Folder.
4: Right click the .epub file and choose open with Sigil (or The Calibre epub Editor is very similar).
5: Often the following message will appear, allow Sigil to fix the epub file:
This EPUB has HTML files that are not well formed or are missing a DOCTYPE, html, head or body elements. Sigil can automatically fix these files, although this may very rarely result in minor data loss in extreme circumstances.
6: The book will open in Sigil and show various files such as title, jacket and a number of chapter files.
7: On the menu bar click Search > Find & Replace.
8: At the bottom of the window copy from this line and paste into the Find box, then copy ' and paste into the Replace box.
9: Ensure that the middle drop down is changed to All HTML files so the find and replace will process all individual HTML files.
10: Observe that hundreds or thousands of replacements have been made.
11: On the File menu Save the file, which will overwrite the original with the modified file.
12: Plug in USB cable to Kobo reader, at message Computer detected touch Connect.
13: The Kobo Reader drive will open showing various files and folders - just minimise or close.
14: Select the modified book and it will highlight in blue.
15: Click the Send to device button - blue arrow.
16: On the Device button choose and click Eject Device then unplug the Kobo reader.
17: Open corrected book in Kobo reader and check the there are no spaces after apostrophes (now single quotes).