Bug Fixes:
I#101 - DAV backends: Limit server requests after getting online (Milan Crha)
I#210 - Global buffer overflow in e_contact_check_attr_type_value_used() (Milan Crha)
I#211 - IMAPx: No IDLE after extraneous connection reset (Milan Crha)
I#212 - EWebDAVSession: Ignore text/plain server responses on success (Milan Crha)
I#213 - camel_mime_filter_backup() calls memcpy(null, ...) (Milan Crha)
I#219 - Search folder content rebuilt after a change in it (Milan Crha)
evo-I#915 - Fix some issues reported by Clang's ubsan sanitizer (Milan Crha)
Miscellaneous:
CamelFilterDriver: do_shell: NULL-terminate the arguments array (Milan Crha)
ECollectionBackend: Limit how often checks for new child sources (Milan Crha)
