3.5.3

New features

[43fe734] Make header sticky in edit and new pages (@javiereguiluz)
[445103f] Replaced deprecated node-sass with sass (@skmedix)

Bug fixes

[149313f] Fix actions deprecation message (@glaubinix)
[b827b8c] Target wrapper element if icon clicked on batch action button (@simonrse)
[cd5fbac] Fix typo in spl_object_hash method name (Sebastian Ewald)
[9f286d2] Do not access primary key on new form (@core23)
[24ec503] Update front-end dependencies to fix misc bugs (@javiereguiluz)
[0252a58] Misc design tweaks and fixes (@javiereguiluz)
[6e0d9f2] Fix some old links in the README file (@aetxebeste)