You can find the changelog for the free version by clicking this link to WordPress.org.
You can find the changelog for the Pro version below:
v3.9.0- 2023-07-20
* Feature: Linked terms: Automatically add terms if main term is added [PRO] #801
* Update: Allow custom input in "Prevent Auto Links Inside elements" [PRO], #1653
* Fixed: Fix Exclude terms from Auto Links not working due to Case sensitivity, #1682
* Update: Add a synonyms option for Auto Terms, #1674
* Update: Make Auto Links Exclude terms bigger and Add Autocomplete to the field, #1680
* Update: Include synonymns consideration when showing suggest terms, #1671
* Update: Prevent a synonym from having the same name as existing terms, #1673
* Update: TaxoFree_ES-IT_TranslationUpdates_June2023, #1675
* Update: TAXO FREE French translation update June 2023, #1678
v3.8.0- 2023-06-15
* Feature: Added TaxoPress Dashboard Page #1136
* Feature: Added term synonyms, ability to use multiple names for one tag [Pro Feature], #174
* Feature: Show synonyms on the Terms screen [Pro Version], #1658
* Feature: Synonyms option for Auto Links [Pro Version], #1656
* Update: Clarify the attachment options for Auto Links, #1623
* Fixed: Related Posts block is broken, #1652
v3.7.4- 2023-05-17
* Fixed: Settings changes not saving, #1635
* Fixed: Auto Links has problems with the & character, #1638
* Fixed: Auto Links has problems with the < > characters, #1637
* Update: Update Pro links to the plugin page, #1636
* Update: Updating Translations ES-FR-IT_TaxoPress 28 April 2023, #1639
v3.7.3- 2023-04-18
* Fixed: 3.7.2 Auto links issue, #1625
* Fixed: "Maximum number of links per post" not working, #1627
* Fixed: Term case isn\'t working, #1622
* Fixed: Fix "Maximum number of links for the same term", #1620
v3.7.2- 2023-04-13
* Fixed: Fatal error on v3.7.1, #1610
* Fixed: Autolink not working with custom taxonomy, #1611
v3.7.1- 2023-04-12
* Fixed: Auto Links not working since 3.7.0 update, #1602
* Fixed: Backslash issues when saving Auto Terms fields, #1601
* Fixed: Taxopress ES, FR, and IT Translation Updates, #1598
v3.7.0- 2023-04-04
* Fixed: Fixed taxonomy default term not working,, #1216
* Fixed: Fixed terms taxonomy not retaining term taxonomy in quick edit, #1395
* Fixed: "<" Characters been stripped out when using Auto Links, #1580
* Fixed: Suggest Terms showing blank space in suggest term metabox, #1583
* Update: Introduced new way to sanitize fields, #1579
* Fixed: Display Terms not listing all terms, #1390
* Fixed: global_term_enabled deprecated error, #1396
* Update: Show private taxonomies terms when using private taxonomy filter in taxonomy screen, #1397
* Update: Move "Remove Terms" options to "Terms" screen from manage terms, #1368
* Update: Remove "Delete Terms" from "Manage Terms", #1367
* Update: Remove manage terms table, #1592
v3.6.7- 2023-03-13
* Fixed: Suggest Terms adds child terms with Classic Editor, #1485
* Update: Allow Private Taxonomies in Auto Terms, #1471
* Update: Suggested improvement for Auto Terms, #1431
* Update: Accessibility improvements to Suggested Terms, #1470
* Fixed: Terms suggestions are not accessible, #1468
* Update: Accessibility improvements for all tabs, #1469
v3.6.6- 2023-03-07
* Update: Increased minimum PHP requirement to PHP 7.2.5, #1553
* Update: PHP 8.1 compatability, #1555
* Fixed: Small fixes to Auto Links, #1459
* Update: Add Support for WP Cron in Auto Terms, #1540
* Update: Improve taxonomy REST API description, #1465
* Fixed: PHP issues with the Pimple version, #1476
v3.6.5- 2023-02-21
* Fixed: Related Posts fatal error with WooCommerce filter, #1484
* Fixed: incorrectly applying the the_title filter by just passing a single parameter, #1545
* Fixed: PHP 8.1 crashing from using taxopress, #1480
* Update: Format option value cleanup, #1531
* Update: Notice warning about languages for Auto Terms and Auto Links, #1546
* Update: TaxoPress-ES-FR-IT-translationUpdate-August23, #1456
* Fixed: Auto link problem with ‘&’ in link #1377
* Fixed: Issues with apostrophes in Auto Links #1444
* Fixed: Warning: array_key_exists expects parameter 2 to be array, bool given #1439
* Update: Add Terms Display "Font size minimum" and "Font size maximum" validation #1354
* Fixed: Span problem on Auto Terms screen #1441
* Update: Update "Automatically fill colors between maximum and minimum" to reflect right label #1371
* Update: FR translation updated #1442
* Fixed: Error with Suggested Terms on post screen #1433
* Added: Allow more than one "Suggest Terms" metabox on post screen #1408
* Update: Shortcode input should be read only. #1420
* Fixed: The title of the metabox is always "automatic term suggestions" #1409
* Update: Small typo in Auto Terms #1410
* Update: Update the plugin description #1405
* Fixed: Plugin breaks on PHP 5.6 #1419
* Added: “Quick Edit” link to the Terms Screen #1359
* Added: Allow users to choose the taxonomy for a term in quick edit #1360
* Added: Filter for Public / Private Terms #1365
* Fixed: Change Taxonomies “Count” link to go to “Terms” screen #1366
* Added: “Post Type” and “Taxonomy” filters to the Terms screen #1358
* Fixed: Remove “Current Post” - Flickr, Technorati and Delicious “dead” links #1374
* Fixed: Extra space in Terms Display and %tag_link% #1375
* Fixed: Link to the Taxonomy from the Terms screen #1364
* Added: A “View” link to terms on the “Terms” screen #1357
* Added: New "Terms" Screen #1260
* Added: Add a Regex Option for Auto Terms #1338
* Fixed: Auto Links feature is hiding the product description #1353
* Fixed: Add "View" links for taxonomies #1334
* Fixed: In the "Existing Content" tab, we can drop the word "all" #1344
* Fixed: Replace "Terms for Current Post" with "Current Post" in menu #1345
* Fixed: Show existing terms only works with Automatic suggestions #1340
* Fixed: Mass edit terms is not saving #1331
* Fixed: Change terms suggestion action handler #1329
* Fixed: Not possible to save "No limit" #1326
* Fixed: Extend Option to limit auto terms schedule action to once per posts to existing content #1323
* Fixed: Option to limit auto terms schedule action to once per posts #1314
* Fixed: TaxoPress Pro seems to require TaxoPress Free #1321
* Fixed: One set of logs reports for a large, slow site #1322
* Fixed: More cautious settings for "Schedule" #1312
* Fixed: Auto Links are processing inside the head tag #1300
* Fixed: Remove "Uncheck this box to disable the "Automatic term suggestions" metabox."" #1305
* Fixed: Mass Edit Terms not working #1304
* Fixed: Add the ability to disable logs #1281
* Fixed: Add the ability to purge the logs #1282
* Fixed: Layout changes for Logs #1297
* Fixed: Translation updates #1289
* Fixed: New filters for Logs #1291
* Fixed: Add a light color for used tags #1287
* Fixed: Small updates for "Edit Terms for Current Post" #1292
* Fixed: "Disable Auto Terms" box not working for scheduling #1284
* Added: Add a Log for Auto Terms #1243
* Fixed: Safeguards auto terms for large sites #1249
* Fixed: Bug with on Suggested Terms #1250
* Fixed: Change "TaxoPress - Settings" to just "TaxoPress" in metabox #1246
* Fixed: Apply Auto terms batches and wait time to scheduled auto terms cron #1241
* Fixed: Ways to process large numbers of posts in Auto Terms #1200
* Fixed: Check compatability of all 3 widgets with WordPress 5.9 #1119
* Fixed: Disable Free version when people install Pro #1234
* Fixed: Tabbed Design for Terms for Current Post screen #1167
* Fixed: Tabbed design for Related Posts screen #1166
* Fixed: Can\'t delete terms in "Manage Terms" #1194
* Fixed: Correct spelling - Terms for Current Post #1134
* Fixed: Enable “Show content from all post types on archive page” by default #1138
* Fixed: Change name "Local tags" to "Existing terms on your site" #1139
* Fixed: Add "Edit this metabox" link #1140
* Fixed: Check "Existing taxonomy terms" by default #1155
* Fixed: Auto Links change “→” to &rarr; #1158
* Fixed: Update "Terms Display" admin screen to use vertical tabs #1116
* Fixed: AShow the Display tags inside the plugin #1121
* Fixed: Small changes to "Terms Display" #1171
* Fixed: Stop making "Post Types" required in Taxonomy #1181
* Fixed: Disabling "Suggest existing terms on your site" causes trouble with other metabox #1174
* Fixed: Disable "Post" option in Auto Terms by default #1178
* Fixed: Suggest terms "show existing terms" changes #1176
* Fixed: Hide dropdown if there is only only option for post suggest terms #1228
* Fixed: Add a refresh button to Automatic term suggestions #1215
* Fixed: Show "Edit this metabox" only to users with "admin simple tags" #1214
* Fixed: Automatic terms suggestions not working with categories #1207
v3.4.3- 2021-12-15
* Fixed: Changes "Terms to Use" to Sources in Auto Terms
* Fixed: Improvement to Auto Terms Screen
* Feature: Add Dandelion and Open Calais to "Auto Terms"
* Fixed: Auto Terms required error
* Fixed: Remove extra space around "Save" button
* Fixed: "Add Auto Terms to existing content" not working for unpublished content
* Fixed: New setting: automatically run "Add terms to existing content"
* Fixed: Uncaught Error: Class \'taxopress_admin_ui\' not found
* Fixed: Auto Terms is buggy with "Existing Content"
* Fixed: TaxoPress doesn\'t handle taxonomies correctly if a plugin is disabled
* Fixed: Allow Auto-Terms to work with imported posts
* Fixed: Enable "Suggest existing terms on your site" by default
* Fixed: Add the registration key to taxonomy dropdowns
* Fixed: Two changes inside "Suggest Terms"
* Fixed: Small typo on "Remove Terms"
* Fixed: Add the option to run "Auto Terms" for different statuses
v3.3.1- 2021-09-20
* Fixed: Fatal error when deleting plugin #889
v3.3.0- 2021-09-20
* Fixed: Auto Links problem with " #824
* Fixed: Posts are auto tagged even when the content does not match the exact term. #602
* Fixed: CSS not working for "Terms for Current Post" div #823
* Feature: Update the menu link for "Auto Terms" #775
* Fixed: Improve the UI for Auto Terms "Keywords list" #822
* Added: Include Spanish translation files #829
* Added: Add Review requests #505
v3.2.2- 2021-09-01
* Fixed: Able to save mandatory field \'Title\' as empty field in Terms for current post. #812
* Fixed: Problem with \' signs in auto links #810
* Feature: Added div class and link class option to Term for Current Post settings #810
* Feature: Added div class and link class option to Term Display settings #810
* Feature: Added div class and link class option to Related Post settings #810
* Feature: Added term link class option to Auto Links settings #810
v3.2.1- 2021-08-23
* Fixed: Notice: Undefined property: WP_Post_Type::$taxonomy on plugin activation #756
* Fixed: Couldn\'t save the related posts \'Title header\' with \'None\' #697
* Fixed: Auto link showing in WordPress admin #772
* Fixed: Remove unused option in TaxoPress screen edit pages. #709
* Fixed: Added exclusion for