Web-Development Work: Odds and Ends

Our previous developer has gone MIA and left some unresolved issues. We need someone who can help us update our existing website and help troubleshoot the existing problems. Here are the specific outstanding issues: 1. When viewing individual posts on the site (as opposed to landing pages) using Chrome on a MacBook Pro, the slider bar disappears. The slider bar appears in other browsers. 2. Our website has a sitewide music player using SoundManager. It was sorta working on mobile except that when people would view posts on an iPhone, the post would automatically jump to the top of the page while they were reading the content. As a result, the player was deactivated in mobile viewing. We'd like our music player to be available on mobile again. Our prior developer mentioned that this issue might require creating some javascript to prevent the "jump to top" from kicking in on ios. 3. Our ads are not loading properly because of issues involving an iframe. 4. We have a two landing pages that are split into separate sections. We'd like it to change the browser url without refreshing the page (i.e. from "[login to view URL]" to "[login to view URL]" - or something like that) once a user scrolls down to a specific section on those two landing pages. 5. We'd like it to start an infinite scroll on the sections at the very bottom of those landing pages (they are currently directed to a new page). 6. We have a recipe index on the site. Currently, users can search by either season OR category. We'd like the ability to search recipes by both season and category at the same time. 7. We use WooCommerce for sales on the site. WooCommerce creates "My account" pages for our customers. We'd like to customize these pages more. Specifically, I'd like to remove some elements from these pages ("order status" and "my addresses"). 8. We need to update to the latest version of Wordpress, but don't want to risk updating it without an experienced developer's assistance and testing on a staging site.