1.24.0 - 2022-07-09

Note that this will be the last 1.x branch release before the 2.x release. We will maintain both branches in parallel for a time; but users are requested to update to version 2.0 once that is fully available.

### Added

- Added `removeComment()` method for Worksheet [PR #2875](https://github.com/PHPOffice/PhpSpreadsheet/pull/2875/files)
- Add point size option for scatter charts [Issue #2298](#2298) [PR #2801](#2801)
- Basic support for Xlsx reading/writing Chart Sheets [PR #2830](#2830)

  Note that a ChartSheet is still only written as a normal Worksheet containing a single chart, not as an actual ChartSheet.

- Added Worksheet visibility in Ods Reader [PR #2851](#2851) and Gnumeric Reader [PR #2853](#2853)
- Added Worksheet visibility in Ods Writer [PR #2850](#2850)
- Allow Csv Reader to treat string as contents of file [Issue #1285](#1285) [PR #2792](#2792)
- Allow Csv Reader to store null string rather than leave cell empty [Issue #2840](#2840) [PR #2842](#2842)
- Provide new Worksheet methods to identify if a row or column is "empty", making allowance for different definitions of "empty":
  - Treat rows/columns containing no cell records as empty (default)
  - Treat cells containing a null value as empty
  - Treat cells containing an empty string as empty

### Changed

- Modify `rangeBoundaries()`, `rangeDimension()` and `getRangeBoundaries()` Coordinate methods to work with row/column ranges as well as with cell ranges and cells [PR #2926](#2926)
- Better enforcement of value modification to match specified datatype when using `setValueExplicit()`
- Relax validation of merge cells to allow merge for a single cell reference [Issue #2776](#2776)
- Memory and speed improvements, particularly for the Cell Collection, and the Writers.

  See [the Discussion section on github](#2821) for details of performance across versions
- Improved performance for removing rows/columns from a worksheet

### Deprecated

- Nothing

### Removed

- Nothing

### Fixed

- Xls Reader resolving absolute named ranges to relative ranges [Issue #2826](#2826) [PR #2827](#2827)
- Null value handling in the Excel Math/Trig PRODUCT() function [Issue #2833](#2833) [PR #2834](#2834)
- Invalid Print Area defined in Xlsx corrupts internal storage of print area [Issue #2848](#2848) [PR #2849](#2849)
- Time interval formatting [Issue #2768](#2768) [PR #2772](#2772)
- Copy from Xls(x) to Html/Pdf loses drawings [PR #2788](#2788)
- Html Reader converting cell containing 0 to null string [Issue #2810](#2810) [PR #2813](#2813)
- Many fixes for Charts, especially, but not limited to, Scatter, Bubble, and Surface charts. [Issue #2762](#2762) [Issue #2299](#2299) [Issue #2700](#2700) [Issue #2817](#2817) [Issue #2763](#2763) [Issue #2219](#2219) [Issue #2863](#2863) [PR #2828](#2828) [PR #2841](#2841) [PR #2846](#2846) [PR #2852](#2852) [PR #2856](#2856) [PR #2865](#2865) [PR #2872](#2872) [PR #2879](#2879) [PR #2898](#2898) [PR #2906](#2906) [PR #2922](#2922) [PR #2923](#2923)
- Adjust both coordinates for two-cell anchors when rows/columns are added/deleted. [Issue #2908](#2908) [PR #2909](#2909)
- Keep calculated string results below 32K. [PR #2921](#2921)
- Filter out illegal Unicode char values FFFE/FFFF. [Issue #2897](#2897) [PR #2910](#2910)
- Better handling of REF errors and propagation of all errors in Calculation engine. [PR #2902](#2902)
- Calculating Engine regexp for Column/Row references when there are multiple quoted worksheet references in the formula [Issue #2874](#2874) [PR #2899](#2899)

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org).
 
 ## 1.24.0 - 2022-07-09
 
+Note that this will be the last 1.x branch release before the 2.x release. We will maintain both branches in parallel for a time; but users are requested to update to version 2.0 once that is fully available.
+
 ### Added
 
 - Added `removeComment()` method for Worksheet [PR #2875](https://github.com/PHPOffice/PhpSpreadsheet/pull/2875/files)