The minor update prevents “external programs from launching in the background when clicking a link inside from Firefox to land them”, check this bug for more details.
Mozilla addresses another issue where users with Screen readers such as JAWS or NVDA unable to navigate through the list of selected extensions in add-ons manager by using up and down arrow keys and the tab button.
The release notes mention this as “Usability improvements to the add-ons manager for users with Screen readers (bug 1567600)”.
The captive portal notification bar doesn’t go away automatically after login is the complete issue has been addressed by Mozilla. “Fixed the captive portal notification bar not being dismissable in some situations after login is complete”.
Mozilla resolved an issue related to Reader Mode in Firefox 69 where Zoom level can’t be increased after a certain point, to solve this, the Firefox team has upped ” max font size in reader mode to match 300% Zoom on default font size”. The changelog mentions this change as “Fixed the maximum size of fons in Reader Mode when Zoomed (bug 1578454)”.
You should know, Firefox dot/period releases are common even with the four-week release cycle, which Mozilla announced today for Firefox.